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Studies  in  Catalysis* 


DISSERTATION 


SUBMITTED  TO    THE    BOARD   OF  UNIVERSITY  STUDIES  OF 

THE  JOHNS  HOPKINS  UNIVERSITY  IN  CONFORMITY 

WITH  THE  REQUIREMENTS  FOR  THE  DEGREE 

OF  DOCTOR  OF  PHILOSOPHY 


BY 


JAMES  M.  JOHNSON 


BALTIMORE 


1907 


EASTON,  PA.  : 
ESCHENBACH  PRINTING  COMPANY. 

1907. 


Studies  in  Catalysis* 


DISSERTATION 


SUBMITTED  TO    THE    BOARD  OF  UNIVERSITY  STUDIES  OF 

THE  JOHNS  HOPKINS  UNIVERSITY  IN  CONFORMITY 

WITH  THE  REQUIREMENTS  FOR  THE  DEGREE 

OF  DOCTOR  OF  PHILOSOPHY 


BY 

JAMES  M.  JOHNSON 

M 

BALTIMORE 
1907 


EASTON,  PA.  : 

ESCHBNBACH  PRINTING  COMPANY. 
1907. 


CONTENTS. 

Page 

Acknowledgment 4 

General  Discussion 5 

On  the  Reactions  between  Thiourazoles  and  Alkyl  Halides 6 

On  the  Rearrangement  of  Acetylhalogenaminobenzene  Derivatives  into 

Halogen  Acetanilide  Derivatives 12 

General  Discussion  of  the  Hydrolysis  of  Amides,  Cane  Sugar,  Oximes, 

and  Esters 44 

On  the  Inversion  of  Cane  Sugar  in  Aqueous  Solutions  of  Acids 51 

On  the  Reactions  of  Carbonyl  Compounds  with  Hydroxylamine  and 

with  Hydroxylamine  Hydrochloride 55 

On  the  Reaction  of  Acetone  with   Phenylhydrazine  and   Phenyl- 

hydrazine  Hydrochloride 80 

On  the  Formation  and  Saponification  of  Esters  and  the  Theory  of  Re- 
versible Catalytic  Reactions 81 

Conclusions 102 

Biographical 103 


186938 


ACKNOWLEDGMENT. 

The  author  takes  pleasure  in  expressing  his  gratitude  to 
President  Remsen,  Professor  Morse,  Professor  Jones,  Professor 
Renouf ,  Associate  Professor  Acree  and  Dr.  Tingle  for  instruction 
in  the  lecture  room  and  laboratory.  Especial  thanks  are  due 
to  Associate  Professor  Acree,  under  whose  personal  direction 
this  investigation  was  made. 


. 
OF  THE     '          \ 

UNIVERSITY  1 

c  r*i  H  1*4  \  r^r 


Studies  in  Catalysis. 


Such  reactions  as  the  saponification  of  esters,  and  the 
hydrolysis  of  amides,  nitriles,  oximes,  cane  sugar,  etc.,  by 
water,  the  formation  of  esters  from  acids  and  alcohols,  and  the 
rearrangement  of  acetylhalogenaminobenzene  derivatives  into 
halogen  acetanilide  derivatives1  are  accelerated  by  acids.  The 
rate  of  transformation  of  the  cane  sugar,  esters  and  amides 
can  be  represented  by  the  following  equation : 

-—  =  KCsub   X  CH  X  CH,o, 

in  which  K  is  the  saponification  constant,  Csub  the  concen- 
tration in  gram  molecules  per  liter  of  the  substance  which  is 
being  hydrolyzed,  CH  the  concentration  of  the  hydrogen  ions 
and  CffzO  the  concentration  of  the  water,  which  in  dilute 
water  solutions  is  practically  constant. 

In  the  hydrolysis  of  amides2  and  oximes  in  dilute 
water  solution  the  amide  and  oxime  and  also  the  hydro- 
gen ions  are  used  up  and  the  •  reaction  appears  to  be 
bimolecular.  In  the  inversion  of  cane  sugar  and  the  sapon- 
ification of  esters  in  dilute  aqueous  solutions,  however,  the 
concentrations  of  the  hydrogen  ions  and  of  the  water  are  not 
appreciably  changed  and  the  reaction  appears  to  be  mono- 
molecular. 

Chemists3  have  long  known  that  we  have  not  data  sufficient 

1  Acree  and  Hinkins:  Am.  Chem.  J.,  28,  370;  Dental  Cosmos,  June,  1901.     Acree 
and  Johnson:  Am.  Chem.  J.,  37,  410. 

*  Ostwald:  J.  prakt.  Chem.,  135,  1  (1883).    Remsen  and  Reid:  Am.  Chem.  J.,  21, 
284.     Reid: /&«*.,  24,  397. 

•  Ostwald:  Z.  physik-  Chem.,  34,  248.     Luther  and  Schilow:  Ibid.,  46,  777.    Weg- 
scheider:  Ibid.,  34,  290.     Wagner:  Ibid.,  28,33.     Slator:  Ibid,  45,512.     Bray:  Ibid., 
54,  463.     Kaufler:   Ibid.,  55,  502.     Walton:  Ibid.,  47,   209.     Erode:  Ibid.,  37,   290. 
Schilow:   Ibid.,  42,  641.     Bredig  and  Ikeda:   Ibid.,  37,  1.     Bredig  and  Walton:  Z.  f. 
Elek.  Chem.,  9,  117.    Bredig  and  Stern:  Ibid., 10,  585.     Bredig:  Ibid.,  11,  528.    Bredig 
and   Haber:    Z.   anorg.  Chem.,  17,  284.     Kastle  and  Loevenhart:    Am.  Chem.  J.,  24, 
491 ;  Ibid.,  29, 397,  563.  Kastle:  Ibid.,  27, 481.  Kastle  and  Clarke:  Ibid., 26, 518.   Kastle, 
Johnston  and  Elvove:  Ibid.,  31,  521.    Kastle  and  Smith:  Ibid.,  32,  376. 


to  tell  from  the  reaction  constants  whether  in  such  reactions 
intermediate  compounds  are  formed  which  are  the  substances 
really  undergoing  transformation.  One  school  has  held  that 
in  such  catalytic  reactions  the  catalyzer  does  not  enter  into 
combination  with  any  substance  present,  but  affects  the  ve- 
locity of  the  reaction  much  as  a  change  of  solvent  does.  An- 
other school,  however,  believes  that  the  velocities  of  some 
reactions  are  increased  or  decreased  because  the  catalyzer 
enters  into  combination  with  some  substance  or  substances 
present  and  the  new  complexes  have  reactivities  different 
from  those  of  the  complexes  from  which  they  were  formed. 
The  object  of  the  present  paper  is  to  discuss  some  of  these  re- 
actions  from  this  latter  point  of  view. 

In  those  reactions  discussed  in  this  communication  it  may 
be  said  that  "When  a  substance  added  to  a  solution  in  which  a 
certain  reaction  is  taking  place  causes  an  increase  or  decrease 
in  the  velocity  of  that  reaction,  without  being  itself  altered  at  the 
end  of  the  reaction,  it  does  so  because  it  unites  to  some  extent- 
with  some  compound  or  compounds  present  and  causes  an  in- 
crease or  decrease  in  the  concentration  of  some  substance  taking 
part  in  the  reaction,  or  because  it  forms  some  new  substance 
(or  substances)  which  yields  the  same  end-products  more  or  less 
readily  than  did  the  substances  in  the  original  solution.  Of 
course,  the  solution  conditions,  such  as  'volume,  sol-vent,  tem- 
perature, etc.,  must  not  be  changed." 

ON   THE   REACTIONS    BETWEEN   THIOURAZOLES    AND    ALKYIv 

HAUDES. 

Phenylthiourazole1  and  phenylurazole,  and  their  salts  react 
with  alkyl  halides  and  form  esters.  In  a  solution  of  an  alkyl 
halide  and  phenylthiourazole  there  are  present  both  molecular 
and  ionized  phenylthiourazole,  and  the  velocity  of  the  re- 
action might  be  proportional  to  the  concentration  of  the  urazole 
ions,  or  to  that  of  the  urazole  molecules,  or  to  both  alike. 

The  reaction  velocity  would  then  be  expressed  by  the  equa- 
tions : 

» Acree:  Am.  Chem.  J.,  27,118;  31,185;  32,606;  37,  71,361;  38,  1.    Ber.d.chem. 
Ges.,  35,  553;  36,  3139;  37,  184,  618. 


-jT  =  KCurwn    X   C  alkyl  halide,  (l) 

-7J  =  KCurmol  salt  X   Ca/^y/  halide,  '       (2) 

or 

-fT  =  KCur    X    Calkyl  halide,  (3) 

depending  upon  whether  the  urazole  ions,  molecules,  or  both 
alike,  react  with  the  alkyl  halide. 
The  salts  are  partly  hydrolyzed, 


UrNa  +  H2O    ^J    NaOH  -h  UrH  (4) 

and  in  a  solution  of  a  thiourazole  salt  and  an  alkyl  halide  the 
alkyl  halide  may  react  with  the  urazole  ions,  the  molecular 
urazole  salt  or  the  free  thiourazole  formed  from  the  salt  by 
hydrolysis.  The  equations  expressing  these  reactions  are 

~7?  —  KCurmol  salt   X    Calkyl  halide,  (5) 

~j7  =  KCUrlon  X   Cafykl  halide,  (6) 

-77  =  KCur  salt  X    Calkyl  halide,  (?) 

•~j7  —  KCur  acid   X    C alkyl  halide,  (8) 

in  which,  as  above,  Calkylhalide  represents  the  concentration 
in  gram  molecules  per  liter  of  the  alkyl  halide  present  at  any 
moment,  Curion  the  concentration  of  the  urazole  ions,  Curmolsalt 
the  concentration  of  the  undissociated  urazole  salt,  and 
Cur  acid  tne  concentration  of  the  undissociated  acid,  and  Cur 
the  total  concentration  of  the  urazole. 

In  order  to  decide  between  these  possibilities  it  is  evidently 
necessary  to  know  the  relative  amounts  of  urazole  ions  and 
molecules  and  the  actual  velocity  of  the  reaction.  In  the 
reaction  between  the  phenyl  thiourazole  and  the  alkyl  halide 


8 

there  was  found  a  gradual  decrease  in  the  value  of  the  constant 
obtained  by  substituting  the  necessary  data  in  the  equation 

/£ 

for  the  reaction  of  the  second  order  TTT  -  r  =  AK    and 


these  constants  were  lowered  very  considerably  by  the  addition 
of  hydrochloric  acid.  It  is  evident  that  the  halogen  acid 
liberated  in  the  reaction, 


UrH  +  C2H5I     53-^     UrC2H5  +  HI, 

suppresses  the  ionization  of  the  phenylthiourazole.  Since  the 
velocity  constant  of  the  reaction  is  also  lowered,  it  would  be 
suspected  at  once  either  that  (i)  the  urazole  ions  are  the  prod- 
uct chiefly  concerned  in  the  reaction  with  the  alkyl  halide 
or  (2)  that  the  halogen  acid  reacts  in  some  way  with  some  of 
the  substances  present  and  lowers  the  reaction  velocity  because 
the  product  formed  by  the  halogen  acid  and  the  other  substance 
can  not  react  so  readily  with  the  alkyl  halide. 

Since  the  addition  of  an  alkali  to  the  solution  of  the  phenyl- 
thiourazole and  the  alkyl  halide  greatly  increases  the  velocity 
of  the  reaction,  and  since  the  salts  of  such  weak  acids  are 
more  highly  ionized  than  the  acids  themselves,  it  would  be 
suspected  at  once  that  the  urazole  ions  are  the  substances 
which  are  chiefly  concerned  in  the  reaction  with  the  alkyl  halide. 
But  such  a  conclusion  would  be  justified  only  in  the  case  that 
absolute  agreement  is  found  between  the  velocity  constants 
and  the  concentration  of  the  ions.  It  may  be  stated  once 
for  all  that  such  agreement  has  been  found  experimentally. 
The  urazole  ions  react  with  the  alkyl  halides  entirely  in  ac- 
cordance with  the  demands  of  the  above  equations.  If  the 
other  urazole  groups  are  concerned  in  the  reaction  it  is  only 
to  a  minor  extent.  Messrs.  Brunei,  Johnson  and  Shadinger 
have  found  that  various  salts  of  the  urazoles  react  with  the 
alkyl  halides  entirely  in  accordance  with  what  is  known  con- 
cerning the  ionization,  hydration,  and  ionic  velocities  of  the 
salts  in  such  solutions. 

The  velocity  constant  of  the  reaction  and  the  ionization  of 
the  urazole  are  both  suppressed  by  the  addition  of  other  sub- 
stances having  an  ion  in  common  with  the  urazole,  whether 


the  urazole  be  in  the  form  of  the  free  acid  or  a  salt.  It  has 
been  found  in  general  that  alkyl  halides  react  with  the  anions 
of  hydroxides,  carbonates,  thiourazoles,  urazoles,  thioacetic  acid 
and  other  substances.  It  should  be  stated  that  it  has  been 
definitely  proved  that  our  results  are  not  in  harmony  with 
the  hypotheses  that  the  alkyl  halides  form  alkyl  derivatives 
(i)  through  intermediate  dissociation  into  alkyl  and  halide 
ions,  as  Lobry  de  Bruyn  and  Steger1  supposed,  (2)  through 

the  union  of  the  alkyl  halide  with  cathions  to  form  the  cathion 

+ 
complexes  M.IC2H5  assumed  by  Kuler,2   (3)  nor  through  the 

intermediate  dissociation  of  the  alkyl  halides  into  a  halogen 
acid  and  an  unsaturated  alkylene  or  aklylidene  residue 


C2H6I     m+     CH3CH:r  +  HI, 

assumed  by  Nef.3  The  hypothesis  might  be  advanced  that 
in  the  reactions  between  alkyl  halides  and  urazoles,  hydroxides, 
carbonates,  etc.,  the  alkyl  halide  unites  with  the  anion  and 
forms  a  very  unstable  complex  anion  which  immediately  de- 
composes into  iodide  ions  and  an  alkyl  urazole,  hydroxide 
or  carbonate  : 


C2H5I  +  OH     m-*-     C2H5I.OH     ^     C^OH  +     . 


Such  an  assumption,  however,  is  purely  gratuitous  and  will 
be  subjected  to  an  experimental  test. 

It  has  been  shown  above,  then,  that  acids,  alkalies  and  salts 
influence  the  above  reactions.  Hydrochloric  acid  and  hydro- 
iodic  acid  act  as  negative  catalyzers  and  lower  the  value  of 
the  velocity  constant  for  the  reaction  between  alkyl  halides 
and  phenylthiourazole,  because  the  halogen  acid  suppresses 
the  ionization  of  the  phenylthiourazole,  and  hence  causes  a 
decrease  in  the  concentration  of  the  urazole  ions,  one  of  the 
two  substances  reacting  according  to  equation  (i).  The 
addition  of  sodium  hydroxide  to  the  solutions  of  the  phenyl- 
thiourazole and  alkyl  halide  causes  an  increase  in  the  velocity 
of  the  reaction  because  the  sodium  hydroxide  reacts  with  the 

1  Rec  trav.  Chim,  18,  311       . 

1  Ber.  d.  chem.  Ges.,  39,  2726. 

«  Ann.  Chem.  (Liebig),  298,  202;  309,  126;  310,  316;  318,  1,  137;  335.  191. 


IO 

phenylthiourazole  and  forms  a  sodium  salt  which  furnishes  the 
solution  with  a  much  greater  concentration  of  urazole  ions 
than  does  the  free  acid.  Likewise,  sodium  iodide  acts  as  a 
negative  catalyzer,  and  lowers  the  velocity  constant,  for  the 
reaction  between  sodium  phenylthiourazole  and  ethyl  iodide, 
because  the  sodium  ions  from  the  sodium  iodide  cause  a  sup- 
pression of  the  ionization  of  the  sodium  phenylthiourazole 
and  a  diminution  of  the  concentration  of  the  urazole  ions. 

The  above  work  then  shows  that  acids,  bases  and  salts  may 
act  as  negative  or  positive  catalytic  agents  for  certain  reactions 
because  they  cause  a  change  in  the  concentration  of  an  inter- 
mediate product  in  the  reaction.  The  intermediate  product 
in  the  above  reaction  between  phenylthiourazole  and  alkyl 
halides  is  the  phenylthiourazole  anion. 

The  following  tables  of  work  by  Mr.  G.  H.  Shadinger  give 
a  short  resume"  o  some  of  the  experimental  results  spoken 
of  above.  A  large  amount  of  work  along  these  lines  has  been 
done  by  Messrs.  R.  F.  Brunei,  J.  M.  Johnson  and  G.  H.  Shad- 
inger, which  will  be  reported  later  in  detail.  The  reaction 
was  followed  analytically  by  titrating  the  unchanged  phenyl- 
thiourazole, or  the  sodium  salt,  with  o.i  N  iodine  solution. 
The  solvent  was  50  per  cent  alcohol  and  the  solution  was  o .  05  N 
with  respect  to  the  phenylthiourazole,  or  sodium  salt,  and  the 
ethyl  iodide.  The  temperature  was  50°.  T  gives  the  time 
in  minutes  and  A  the  number  of  cc.  o .  i  N  iodine  solution  re- 
quired to  titrate  20  cc.  of  the  solution  at  the  beginning.  A — x 
is  the  unchanged,  and  x  the  transformed  urazole  and  ethyl 
iodide,  expressed  in  cc.  o.i  N  iodine.  AK  is  the  constant 

calculated  for  a  bimolecular  reaction,  AK  —    ,  •       on 

the  assumption  that  A  is  equal  to  5  cc.  o.  i  N  iodine. 

50°;  0.05  N  i-Phenyl-3-thiourazole;  and  0.05  N  ethyl  iodide. 

T.  A.  A  —  *,  x.  AK. 

5  4.90  4. ii  0.79  0.039 

10  4.90  3.57  1.33  0.038 

15  4-90  3-18  1.72  0.037 

31  4-90  2.46  2.44  0.033 

60  4.90  1.88  3.02  0.027 

120  4.90  1.29  3.61  0.024 

240  4.90  0.66  4.24  0.027 


II 

5O°;o.o5  N  i-Phenyl-3-thiourazole;  0.05  N  ethyl  iodide;  and 
0.25  N  HC1. 

T.  A.  A  — x.  *.  AK. 

60  4.71  3.54  I.I7  0.00584 

The  first  table  shows  the  constant  decrease  in  the  value  of 
AK  as  the  reaction  proceeds,  due  to  the  increasing  suppres- 
sion of  the  ionization  of  the  phenylthiourazole  by  the  hydro- 
iodic  acid  formed  in  increasing  amount  as  the  reaction  pro- 
ceeds. The  second  table  shows  very  sharply  the  great  de- 
crease, caused  by  the  5  molecules  of  hydrochloric  acid,  in  the 
ionization  of  the  phenylthiourazole  and  the  consequent  de- 
crease in  the  velocity  constant  of  the  reaction.  The  halogen 
acids  act  as  negative  catalyzers  because  they  cause  a  decrease 
in  the  concentration  of  the  urazole  ions,  and  a  consequent 
decrease  in  the  velocity  of  the  reaction. 

50°;  o.i  N  Sodium  i-Phenyl-3-thiourazole;  and  o.i  N  ethyl 
iodide. 


T. 

A'. 

A'—  x. 

X. 

A'K'. 

AK. 

IO 

9-44 

3.80 

5.64 

0.156 

O.O78O 

20 

9-44 

2.26 

7.18 

0.168 

O.084O 

40 

9-44 

1.30 

8.14 

0.165 

0.0825 

81 

9-44 

0.70 

8.74 

0.163 

O.O8I5 

190 

9-44 

0.30- 

9.14 

0.169 

0.0845 

In  this  table  AK  represents  the  velocity  which  the  reaction 
would  have  if  the  concentrations  were  the  same  as  in  the  above 
reaction  between  the  phenylthiourazole  and  ethyl  iodide. 

This  table  shows  that  the  velocity  constant  for  the  reaction 
between  the  sodium  thiourazole  and  the  ethyl  iodide  is  twice 
as  great  as  that  for  the  reaction  between  the  phenylthiourazole 
and  the  ethyl  iodide,  because  the  sodium  salt  is  more  highly 
ionized.  It  was  shown  in  other  experiments  that  the  addi- 
tion of  sodium  iodide  or  sodium  chloride  to  the  solution  causes 
a  decrease  in  the  velocity  constant  with  the  decrease  in  the 
percent  of  ionization  of  the  sodium  phenylthiourazole.  The 
sodium  iodide  and  sodium  chloride  act  as  negative  catalyzers 
because  they  cause  a  decrease  in  the  concentration  of  the 
urazole  ions,  and  a  consequent  decrease  in  the  velocity  of 
the  reaction. 


12 

The  following  table  worked  out  by  R.  F.  Brunei  and  J.  M. 
Johnson1  shows  that  potassium  iodide  acts  as  a  negative 
catalyzer  in  the  reaction  between  potassium  i-phenyl-4- 
methylurazole  and  ethyl  iodide  in  40  per  cent  alcoholic  solu- 
tion at  60°.  The  solutions  are  0.3  N  with  respect  to  the  ethyl 
iodide,  potassium  i-phenyl-4-methylurazole,  and  the  potas- 
sium iodide  added.  The  second  and  third  columns  contain 
the  percent  of  ethyl  ester  formed  and  the  values  of  AK  when 
no  potassium  iodide  is  added  to  the  solution,  while  the  fourth 
and  fifth  columns  give  the  per  cent  of  ester  formed  and  the  value 
of  AK  when  one  molecular  quantity  of  potassium  iodide  is 
added  to  the  solution.  It  is  clear  that  the  potassium  iodide 
acts  as  a  negative  catalyzer  because  it  causes  a  decrease  in 
the  per  cent  of  ionization  of  the  potassium  i-phenyl-4-methyl- 
urazole. 

0.3  N  Potassium  urazole  +  0.3  N       0.3  N  Potassium  urazole  +  0.3  N  ethyl 
ethyl  iodide.  iodide  +  0.3  N  potassium  iodide. 


Time  in 
hours. 

Per  cent 
reacted. 

AK. 

Per  cent 
reacted. 

AK. 

0-5 

18.00 

0.44 

12-9 

0.30 

1.0 
2.O 
4.0 

30.35 
48.20 
62.85 

0-45 
0.46 
0.42 

23-9 
40.0 

52.9 

0.31 

0-33 
0  28 

ON    THE    REARRANGEMENT    OF    ACETYLHALOGENAMINOBENZENE 
DERIVATIVES  INTO  HALOGEN  ACETANILIDE  DERIVATIVES. 

But  even  in  some  cases  in  which  it  is  not  easy  to 
measure  the  small  amounts  of  intermediate  product  present, 
it  will  be  found  possible  to  prove  by  the  qualitative  and  quan- 
titative study  of  the  reactions  that  such  are  present. 

Acetylhalogenaminobenzene2  derivatives  rearrange  in  the 
presence  of  halogen  acids  into  halogen  acetanilide  derivatives, 


CH8CONC1C6H5    »-*-     CHSCONHC6H4C1, 

but  are  stable  in  the  presence  of  alkalies.     The  reaction  is  not 
appreciably    reversible.     That    the    reaction    is    not    brought 

>  Acree:  Am.  Chem.  J.,  37,  71. 

*  Slosson:  Ber.  d.  chem.  Ges  ,  28,  3265.     Armstrong:  J.  Chem.  Soc.  77,  1047.     Chat- 
taway  and  Orton:  Ibid.,  75.  1046;  77,  134;  79,  274;  etc. 


13 

about  by  the  mere  presence  of  hydrogen  ions1  is  shown  by  the 
fact  that  acetylchloraminobenzene  in  16  per  cent  acetic  acid 
solution  at  o°  is  rearranged  about  1,000  times  as  rapidly  by 
hydrobromic  acid  of  a  given  concentration  as  by  hydrochloric 
acid  in  the  same  concentration.  Furthermore,  the  acetic  acid 
present  in  the  solution  furnishes  1.5  times  as  much  hydrogen 
ions  as  the  hydrochloric  acid,  but  the  velocity  of  rearrangement 
in  the  dilute  acetic  acid  is  very  much  smaller  than  when  hy- 
drochloric acid  is  present.  Furthermore,  a  sample  of  pure 
acetylchloraminobenzene  which  stood  several  days  under 
dilute  sulphuric  acid  was  recovered  unchanged  and  99  per- 
cent pure,  with  the  melting  point  88°.  Another  proof  that 
the  rearrangement  is  not  caused  by  the  mere  presence  of 
hydrogen  ions  is  furnished  by  the  fact  that  acetylchloram- 
inobenzene in  ligroin  is  changed  almost  instantly  by  chlorine 
and  bromine  into  parachloracetanilide  or  parabromacetan- 
ilide. 

Still  further  proof  that  the  rearrangement  is  not  caused 
by  the  mere  presence  of  the  hydrogen  ions,  but  involves  the 
union  of  the  hydrogen  ions  and  halogen  ions  with  the 
acetylchloraminobenzene  is  furnished  by  the  order  of  the 
reaction  and  the  qualitative  and  quantitative  study  of  the 
course  and  nature  of  the  reactions. 

Blanksma2  found  that  in  the  rearrangement  of  acetylchlor- 
aminobenzene by  hydrochloric  acid, 


CH8CONC1C6H5  +HC1      *-*•     CH3CONHC6H4C1  +  HC1, 

the  velocity  is  proportional  to  the  concentration  of  the  acetyl- 
chloraminobenzene and  to  the  square  of  the  concentration  of  the 
hydrochloric  acid.  The  concentration  of  the  hydrochloric  acid 
remains  constant  since  it  is  not  used  up  in  the  reaction.  The 
constant  obtained  is  that  for  a  monomolecular  reaction,  which 
shows  that  the  acetylchloraminobenzene  is  the  only  substance  un- 
dergoing change  in  concentration.  The  fact  that  the  reaction 
is  monomolecular  proves  that  the  rearrangement  is  intra- 
molecular and  not  intermolecular.  If  the  reaction  involved 

1  Acree  and  Johnson:  Am.  Chem.  J.,  37,  410. 
1  Rec.  trav.  Chim.,  21,  366;  22,  290. 


14 

the  chlorinatibn  of  the  benzene  nucleus  in  one  molecule  by 
the  halogen  amino  group,  or  some  derivative,  of  another  mol- 
ecule the  reaction  would  be  bimolecular,  or  of  a  higher  order. 
This  will  be  discussed  in  detail  below.  In  nearly  all  catalytic 
reactions  studied  heretofore,  such  as  the  hydrolysis  of  esters, 
inversion  of  cane  sugar,  hydrolysis  of  amides,  etc.,  the  veloc- 
ity of  transformation  has  been  found  to  be  simply  proportional 
to  the  concentration  of  the  hydrogen  ions.  These  two  different 
cases  are  very  important  in  that  they  throw  light  on  the  the- 
ory of  catalysis  in  general  and  in  that  they  make  it  possible  to  deter- 
mine, in  cases  where  only  a  small  amount  of  the  intermediate 
compound  or  salt  is  present,  whether  the  substance  under- 
going transformation  is  the  undissociated  salt  or  the  ionic 
form  of  the  salt.  The  acetylchloraminobenzene  is  probably 
a  very  much  weaker  base  than  acetamide  on  account  of  the 
negative  phenyl,  acetyl  and  bromine  groups  attached  to  the 
nitrogen,  and  its  salts  will,  therefore,  be  greatly  hydrolyzed 
in  aqueous  solutions.  Furthermore,  the  small  amount  of  salt 
actually  existing  will  be  nearly  completely  dissociated  in  the 
extremely  dilute  solution.  It  follows  then  that  the  hydrolysis 
of  the  salt  will  follow  the  familiar  equation  of  Arrhenius1  and 
Walker,2 

CH3CONC1C6H5  +  H     ^     CH8CONHC1C6H5 

ps- 

(Chal X)  +  CH      =      KhydCsalt  dts       =       J7^-Csalt  dis,       (l) 

&b 

in  which  Chal  represents  the  original  concentration,  in  gram 
molecules  per  liter,  of  the  acetylhalogenaminobenzene  deriva- 
tive used,  x  the  concentration  of  this  substance  changed 
into  other  products,  including  the  complex  salt,  (Chal — x) 
the  concentration  of  the  acetylchloraminobenzene  derivative 
at  the  moment  equilibrium  is  established,  CH  the  concentration 

of  the  hydrogen  ions,  Csaltdls  the  concentration  of  the  complex 

+ 
cathion,   CH3CONHC1CCH5,    Kkvd     the     hydrolysis    constant, 

Kw  the  ion  product  of  water  at  the  temperature,  and  Kb  the 

i  Z.  physik.  Chem.,  5,  1;  13,  407. 
»/WJ.,4,319;32,137.    J.  Chem.  Soc.,  77, 5. 


15 

affinity  constant  of  the  weak  base.  The  value  of  Csaltdis 
can  be  calculated  for  all  dilutions  when  Kb  and  the  dissoci- 
ation constant  for  the  salt  become  known.  Kb  is  too  small  to 
be  measured  accurately,  by  the  methods  now  at  hand,  but 
this  will  be  studied  later.  Since  only  a  very  small  amount 
of  the  acetylchloraminobenzene  and  of  the  hydrogen  ions  are 
used  up  in  forming  the  salt,  (Chal — x)  and  CH,  are  so  nearly 
equal  to  the  concentrations  that  these  two  would  have  if  no 
salt  were  formed,  that  no  appreciable  error  is  involved  in  sub- 
stituting for  the  values  of  (Chal — x)  and  CH  in  equation  (i) 
before  any  rearrangement  occurs,  the  values  of  the  concentra- 
tions that  these  two  would  have  if  either  were  alone  in  the 
solution.  The  same  may  be  said  for  other  cases  considered 
below,  as  has  been  discussed  by  Walker,  and  this  point  will 
not  be  considered  again.  If  the  dissociated  salt  were  the  only 
substance  rearranging  into  parachloracetanilide  the  rate  of 
formation  of  the  parachloracetanilide  would  be 

CH3CONHC1C6H5     m+     CH3CONHC6H4C1  +  H 

— dCsaitdis  dx  v       r  f  \ 

T7 =       — TT       =       **•  trans***  salt  dtst  \"2) 

at  at 

in  which  Ktrans  is  the  velocity  constant  for  the  rearrange- 
ment of  the  dissociated  salt  which  is  present  in  the  concen- 
tration Csalfd{s.  —dCsaltdis  is  the  small  amount  of  Csaltdis 
which  rearranges  in  the  time  dt.  — dCsaltdis  is  exactly  equal, 
in  gram  equivalents,  to  dx,  the  small  amount  of  product  formed 
by  the  rearrangement  of  the  acetylhalogenaminobenzene.  We 
may,  therefore,  write  dx  for  the  small  amount  of  substance 
transformed,  whether  it  be  the  intermediate  compound  or  the 
acetylhalogenaminobenzene.  The  dx  represents  an  increase 
and  the  dCsaltdis  a  decrease;  hence  the  one  is  the  negative 
of  the  other. 

In  the  total  reaction,  expressed  by  equations  (i)  and  (2), 
we  are  dealing  with  two  consecutive  reactions.  The  first  is 
a  reversible  reaction  involving  what  may  be  considered  prac- 
tically a  bimolecular  and  a  unimolecular  reaction.  The  second 
is  a  non-reversible  bimolecular  reaction.  The  concentration  of 


16 

Csalt  dis  at  any  moment  depends  upon  the  concentrations  of  the 
acetyl  halogenatninobenzene,  hydrogen  ions,  and  anions,  and 
upon  the  velocities  of  the  two  reactions.  The  first  reaction  is  the 
neutralization  of  the  base  by  an  acid,  and  all  such  reactions  take 
place,  as  a  rule,  immeasurably  rapidly.  The  second  reaction 
is,  therefore,  very  slow  in  comparison  with  the  first,  and  the 
equilibrum  expressed  in  equation  (i)  is  never  appreciably 
disturbed  by  the  change  in  the  concentration  of  Csaltdis  in 
reaction  (2).  Hence  according  to  (i) 

Csaltdis      =      -^-(Chal  -  X)   X   Cff, 

XV  iu 

and  equation  (2)  becomes 

dX  K  trans  Kb      ,  ^  ^\    ^/    /- 

-ft  --       —g-    -  (Chai  —  x)  ><  Cff, 
or 

Kb^trans  TS  s  _N 


T  r  \  v  '         v 

tCff  (Lhal  -  X)  Kw 

If  the  base  existed  entirely  as  salt  the  velocity  of  rearrange- 
ment would  be  Ktrans  ;  but  since  only  a  small  fraction  of  the 
base  exists  as  salt,  the  reaction  is  retarded  and  the  value  of 
the  constant  actually  obtained  for  the  rate  of  transformation 
of  the  acetylchloraminobenzene  is  the  value  of  the  real  veloc- 
ity constant  for  the  substance  actually  changing  into  the  para- 
chloracetanilide  divided  by  the  ratio  of  the  amount  of  base 
to  the  amount  of  dissociated  salt.  But  according  to  equation 
(3)  this  constant  should  be  proportional  to  the  concentration 
of  the  hydrogen  ions.  Experimentally,  however,  it  is  found 
that  the  constant  varies  as  the  square  of  the  concentration 

of  the  hydrogen  ions.     It  is,  therefore,  certain  that  the  ion 

+ 
CH3CONHC1C6H5  is  not   the   substance   which   chiefly   yields 

the  parachloracetanilide,  although  it  may  do  so  to  a  very  small 
extent.  We  must  look  elsewhere  then  for  the  substance  which 
changes  directly  into  parachloracetanilide. 

Since  the  amount  of  molecular  salt  present  is  very  small, 
the  formation  of  this  undissociated  salt  will  follow  the  require- 


17 

ments  of  the  mass  law  as  discussed  above  for  the  complex 
cathion  and  give  equation  (4) 

CH3CONC1C6H5  +  H  -f  ci    ^     CH3CONHC12C6H5 

{Chal  —  -*0    X  Cff  X   Cci      :==i 

a g -Csalt,und=  (Chal  •*)  X  C?H(CI),  (4) 

in  which  Kaffin  is  the  dissociation  constant  of  the  salt,  the 
molecular  form  of  which  has  the  concentration  Csaltund. 

If  the  undissociated  salt  yields  the  parachloracetanilide 
the  rate  of  transformation  of  the  acetylchloraminobenzene 
would  be  expressed  by  the  equation 


CH3CONHC12C6H6    .m+     CH3CONHC8H4C1  +  HC1 

d  CSalt  und 


dt  dt 


—       KtransC salt  und*  (5) 


It  is  evident  from  (4)  that  instead  of  CsaU  und  in  (5)  we  can 
substitute 

Kh 

f  r*  &  \  \/  r^     *^  r*      /^** 


K    K  m 

and  we  then  obtain 


-^\    xx    /"•       \x    r> 
-  X)    X    tff  X    La      = 


A.W&*  affin 

or 


(Chal  -  X)    X    C2ff(Cl)t       (6) 


1  -  Chal  KtransKb 


ir(  Cl)  (  Chal  -  X)  Kw  Kaffin 

But  equation  (6)  expresses  the  results  actually  obtained  ex- 
perimentally. In  other  words,  the  velocity  of  the  reaction 
shows  that  the  substance  undergoing  change  is  the  undisso- 
ciated salt  in  (4)  and  not  the  cathion  of  this  salt  in  (i).  In 


i8 

entire  harmony  with  this  is  the  fact  that  different  acids 
(HC1,  HBr,  H2SO4,  CH3COOH)  do  not  give  reaction  constants 
bearing  the  relation  to  the  concentration  of  their  hydrogen  ions 
demanded  by  equation  (3).  All  of  these  acids  would  give 
the  same  complex  cathion  in  (i).  The  amount  of  this  cathion 
and  consequently  the  rate  of  transformation  of  the  acetyl- 
chloraminobenzene,  should  be  strictly  proportional  to  the  con- 
centration of  the  hydrogen  ions,  whatever  the  acid,  if  the  re- 
action took  place  according  to  (i).  Such,  however,  is  not 
the  case. 

The  fact  that  three  different  acids  give  different  velocity  con- 
stants is  predicted  by  theory  if  equation  (5)  represents  the 
method  of  change.  The  undissociated  salts  formed  by  all 
of  these  acids  can  be  represented  by  CH3CONHClAcCcH5 
in  which  Ac  represents  the  anion  of  the  acid.  These  different 
salts  would  be  expected  to,  and  do,  have  different  velocities 
of  transformation  as  will  be  discussed  below.  Instead  of  the 
salt  represented  in  the  equation  (4)  another  compound,  to 
give  a  general  illustration  applicable  in  other  cases  as  well  as  in 
the  present  one,  could  be  formed  by  the  addition  of  two  anions 
or  two  cathions  to  the  acetylchloraminobenzene  as  follows : 

CH3CONC1C6H5  +  2Ac  ^t     CH3CONCl(Ac)2C6H6 ; 
CHSCONC1C6H6  +  2H     ^t     CH8CONC1H2C6H5; 

CH3CONC1H2C6H5     »->-     CH3CONHC6H4C1  +  2H. 

This  would  lead  to  the  same  velocity  constants  as  in  equation 
(6)  and  as  the  present  work  does  not  decide  absolutely  between 
these  two  we  shall  confine  our  discussion  of  the  case  as  if  it  took 
place  according  to  equations  (5)  and  (6)  as  it  most  probably 
does. 

The  quantitative  evidence  leads  to  the  belief  that  acetyl- 
chloraminobenzene does  not  rearrange  per  se  in  the  above 

reactions.      The    evidence    further    shows    that    the    positive 

+ 
ion  in  equation  (i),  CH3CONHC1C18H6  is  not  the   substance 

undergoing  transformation  into  parachloracetanilide,  but  that 


19 

the  undissociated  salt  CHgCONHCLAjHg  changes  into  para- 
chloracetanilide  and  hydrochloric  acid. 

What  is  the  evidence  supporting  the  view  that  such 
a  substance,  present  in  only  a  very  small  amount  at  any  mo- 
ment, can  change  rapidly  enough  to  account  for  the  reaction 
velocity? 

Jackson  and  Clarke1  and  also  Fries2  have  shown  that  (CH3)2 
NBr2C6H5  and  other  similar  substances,  which  are  entirely 
analogous  to  the  above  salt,  rearrange  very  rapidly  into  para- 
bromdimethylaniline  hydrobromide. 

The  following  evidence  leaves  no  doubt  that  the  above  is 
the  correct  interpretation  of  the  reaction.  If  the  acetylhalo- 
genaminobenzene  adds  the  halogen  acid  as  illustrated  above, 
we  should  obtain  the  same  intermediate  product  from  acetyl- 
chloraminobenzene  and  hydrobromic  acid  as  is  formed  by  the 
action  of  hydrochloric  acid  on  acetylbromaminobenzene : 

(A)  CH3CONC1C8H6  -f-  HBr     * 

£  CH3CONHClBrC6H5  **+ 

(B)  CH3CONBrC6H6  +  HC1     4PT 

CH3CONHC6H4Br  +  HC1. 

If  this  addition  product  is  the  substance  which  rearranges 
into  the  parahalogenacetanilide,  we  should  obtain  the  same 
substance  or  substances  by  either  of  these  methods,  and  the 
relative  amount  of  parachloracetanilide  and  parabromacet- 
anilide  formed  would  depend  upon  the  relative  tendency 
of  the  chlorine  and  bromine  to  enter  the  benzene  nucleus. 
It  was  known  beforehand  that  acetylbromaminobenzene  re- 
arranges very  much  more  rapidly  into  parabromacetanilide 
than  the  corresponding  chlor  derivative  yields  parachloracet- 
anilide ;  we  therefore  predicted  that  from  both  of  the  reactions 
we  should  obtain  the  same  product,  parabromacetanilide, 
and  this  was  happily  verified  by  experiment.  The  parabrom- 
acetanilide obtained  seemed  to  be  practically  free  from  para- 
chloracetanilide. The  formation  of  the  parabromacetanilide 
from  acetylchloraminobenzene  and  hydrobromic  acid  takes 

* Am.  Chem.  J.,  34,  261;  36,  409. 
*  Ann.  Chem.  (Liebfe),  346,  128. 


20 

place    according   to    a  reaction   of   the    second  order  as  de- 
manded by  equation  (A)  above. 

We  have  further  found  that  when  bromine  or  chlorine  is 
added  to  acetylchloraminobenzene  in  ligroin  the  substance  is 
transformed  in  a  few  seconds  into  parabromacetanilide  and 
parachloracetanilide.  The  formation  of  the  parabromacet- 
anilide was  predicted. 

CH3CONC1C6H6  +  Br2     »->•      CH3CONClBr2C6H6     m+ 

CH3CONHC6H4Br  -j-  BrCl; 

CH3CONC1C6H5  +  C12     «-*-     CH.CONC1.C.H.     «-*• 

CH3CONHCflH4Cl  +  C12. 

The  transformation  of  these  acetylhalogenaminobenzenes 
in  the  presence  of  acids  was  effected  in  aqueous  acetic  acid 
solutions.  If  the  cathion  in  (i)  were  the  substance  being 
transformed  into  parahalogenacetanilide  this  rearrangement 
should  take  place  more  rapidly  in  those  solutions  containing 
more  water,  because  in  such  solutions  the  salt  would  be  more 
completely  dissociated.  But  if  the  undissociated  salt  in  (5) 
is  the  substance  being  changed  into  the  halogenacetanilide 
the  rearrangement  should  take  place  more  slowly  in  those  solu- 
tions containing  more  water,  because  there  would  be  less  un- 
dissociated salt  in  the  solutions  containing  more  water.  Since 
the  concentration  of  the  undissociated  salt  would  be  smaller 
the  velocity  of  transformation  of  the  acetylhalogenamino- 
benzene  would  be  smaller.  Since  the  rearrangements  take  place 
more  slowly  in  those  solutions  containing  more  water,  the 
latter  hypothesis  and  equations  (5)  and  (6)  are  verified. 

Finally,  if  the  undissociated  salt  were  the  substance  being 
transformed  the  addition  of  a  salt  with  a  common  ion  should 
cause  a  rise  in  the  velocity  of  transformation.  It  is  evident 
that  the  addition  of  potassium  chloride  to  a  solution  of  the 
acetylchloraminobenzene  and  hydrochloric  acid  would  cause 
a  suppression  of  the  ionization  of  the  complex  hydrochloride. 
If  the  undissociated  salt  is  the  substance  being  transformed 
it  is  evident  that  the  increase  of  the  concentration  of  this  sub- 
stance by  the  potassium  chloride  should  cause  an  increase  in 
the  reaction  velocity.  The  theory  has  been  fully  verified 


21 

experimentally  as  will  be  shown  below.  If  the  complex  ca- 
thion  were  the  substance  undergoing  transformation  the  ad- 
dition of  potassium  chloride  should  cause  a  decrease  in  the 
ionization  and  velocity  of  reaction,  provided  that  the  potas- 
sium chloride  does  not  act  per  se  as  an  energetic  positive 
catalyzer.  Such  is,  however,  not  the  case. 

It  is  entirely  possible  that  the  rearrangements  of  deriva- 
tives of  phenylnitramine,  phenylnitrosamine,  and  phenyl- 
sulphaminic  acid  into  derivatives  of  nitraniline,  nitrosoaniline 
and  sulphanilic  acid  take  place  like  the  above  reactions,  and 
this  will  be  a  subject  of  investigation  in  this  laboratory. 

EXPERIMENTAL. 

The  acetylchloraminobenzene  and  the  acetylbromamino- 
benzene  used  in  the  following  experiments  were  prepared 
by  Slosson's1  method,  as  the  methods  of  Chattaway  and  Orton2 
and  of  Armstrong3  were  tried  without  good  results. 

Five-tenths  gram  of  acetylchloraminobenzene,  melting  at  85°- 
87°,  was  dissolved  in  ligroin  and  0.25  cc.  of  bromine  were 
dropped  in;  a  white  precipitate  of  parabromacetanilide  was 
formed  immediately.  This  was  filtered  off  after  a  few  moments, 
dried  and  recrystallized  from  alcohol.  It  melted  at  163°- 
167°;  when  mixed  with  pure  parabromacetanilide,  m.  p.  167°, 
obtained  by  another  method,  the  melting-point  was  not  low- 
ered. 

One-half  gram  of  acetylchloraminobenzene,  m.  p.  85°-87°, 
was  dissolved  in  ligroin  and  a  rapid  stream  of  dry  chlorine 
gas  was  passed  in.  After  one  minute  a  white  precipitate  of 
parachloracetanilide  began  to  appear.  When  the  precipi- 
tation was  complete,  the  substance  was  filtered  off,  dried,  and 
recrystallized  from  alcohol.  It  melted  at  i73°-i76°.  When 
mixed  with  parabromacetanilide,  m.  p.  167°,  it  melted  at 
i65°-i7o°.  When  mixed  with  pure  parachloracetanilide,  m.  p. 
I76°-I78°,  made  from  acetylchloraminobenzene  and  hy- 
drochloric acid,  it  melted  at  i76°-i78°. 

Acetylchloraminobenzene,   m.   p.    85°-87,°    was    dissolved 

1  Loc  cit 

*Ibid. 

•Ibid. 


22 

in  glacial  acetic  acid  and  treated  with  dilute  hydrochloric  acid. 
A  white  precipitate  of  parachloracetanilide  was  obtained  which, 
when  crystallized  from  alcohol,  melted  at  i76°-i78°. 

Acetylchloraminobenzene,  m.  p.  85°-87°,  was  dissolved 
in  glacial  acetic  acid  and  treated  with  dilute  hydrobromic 
acid.  A  white  precipitate  of  parabromacetanilide  was  obtained 
which  melted  at  i65°-i67°  when  crystallized  from  alcohol. 
When  mixed  with  parabromacetanilide,  m.  p.  167°,  obtained 
from  acetylbromaminobenzene  and  hydrobromic  acid  the  melt- 
ing-point was  still  i65°-i67°.  When  mixed  with  pure 
parachloracetanilide,  m.  p.  I76°-I78°,  the  melting-point 
was  lowered  to  I5o°-i6o°. 

One  gram  of  acetylchloraminobenzene,  m.  p.  85°-87°, 
was  treated  with  a  large  excess  of  dilute  sulphuric  acid  and 
let  stand  two  weeks.  The  product  was  filtered  off  and  recrys- 
tallized  from  alcohol.  It  then  melted  at  88°-89°.  A  sam- 
ple of  0.2927  gram  required  28.80  cc.  of  0.1185  N  sodium 
thiosulphate  solution.  The  substance  then  was  unchanged 
acetylchloraminobenzene,  99  per  cent  pure.  This  experi- 
ment shows  that  sulphuric  acid  causes  only  a  very  slow  change 
in  the  substance.  Quantitative  experiments  given  below 
show  further  that  this  change  is  very  slow  when  the  acetyl- 
chloraminobenzene and  sulphuric  acid  are  dissolved  in  aque- 
ous acetic  acid.  The  experiment  proves  very  clearly  that 
the  catalysis  is  not  due  to  the  mere  presence  of  the  hydro- 
gen ions,  because  the  rapidity  of  rearrangement  caused  by  the 
sulphuric  acid  in  a  given  concentration  is  very  much  less 
than  that  produced  by  an  equal  concentration  of  hydro- 
chloric acid  or  hydrobromic  acid. 

Acetylbromaminobenzene,  m.  p.  88°,  was  treated  with  di- 
lute hydrochloric  acid.  A  white  precipitate  of  parabromacet- 
anilide was  obtained  which,  when  recrystallized  from  alcohol, 
melted  at  167°,  and  this  melting-point  was  not  lowered  by 
mixing  the  sample  with  parabromacetanilide  obtained  other- 
wise. 

Acetylbromaminobenzene,  m.  p.  88°,  was  treated  with 
dilute  hydrobromic  acid.  A  precipitate  of  parabromacet- 
anilide was  obtained  which,  when  recrystallized  from  alcohol, 


23 

melted  at  167°.  The  melting-point  was  not  lowered  by  mix- 
ing the  sample  with  the  above  compound,  or  with  pure  para- 
bromacetanilide  obtained  otherwise. 

Paratolylacetylnitrogenbromide,  prepared  by  Chattaway  and 
Orton's  method,  rearranged  so  quickly  on  standing,  or  when 
treated  with  hydrochloric  or  hydrobromic  acid,  that  it  was 
impossible  to  do  any  quantitative  work  with  this  substance. 

The  paratolylacetylnitrogenchloride  used  in  the  rearrange- 
ment experiments  was  prepared  by  Chattaway  and  Orton's 
method.  This  substance,  when  treated  with  hydrochloric 
acid,  gave  a  mixture  of  paracettoluidide  and  orthochlor- 
paracettoluidide. 

Paratolylacetylnitrogenchloride,  when  treated  with  a  large 
excess  of  hydrobromic  acid,  gave  a  red  oil  from  which  a  com- 
pound was  obtained  by  recrystallization  from  alcohol.  This 
melted  at  io7°-io8°  and  was  probably  impure  orthobrom- 
paracettoluidide,  m.  p.  118°. 

Paratolylacetylnitrogenchloride,  in  ligroin  solution,  was 
decomposed  by  bromine  and  chlorine,  giving,  in  both  cases, 
apparently  some  impure  paracettoluidide,  melting  at  140°- 
150°. 

REARRANGEMENT   EXPERIMENTS. 

Experiments  with  Hydrobromic  Acid. 

If  in  the  reaction  between  hydrobromic  acid  and  acetyl- 
chloraminobenzene  the  parabromacetanilide  is  formed  by 
the  rearrangement  of  the  undissociated  hydrobromide  of 
the  acetylchloraminobenzene,  the  equations  wil  differ  some- 
what in  form  from  those  used  in  the  work  on  the  rearrange- 
ments produced  by  hydrochloric  acid.  If  the  undissoci- 
ated salt  is  formed  according  to  the  mass  law  we  have 

CH3CONC1C6H5  +  H  +  Br      ^ 

CH3CONHClBrC6H5    »•*• 

CH3CONHCflH4Br  +  H  +  Cl. 
Csaltundt    (i) 


or,  when  y  is  small  in  comparison  with  x, 


24 

f  r*  *    \f/~<  \/~*  Baffin  KM   ~  f    . 

((-hal  -  X)(LBr  -  X)Lff      =      -  ^  -  (-salt  und,  (2) 


in  which  y  is  the  concentration  of  the  salt  formed,  and  x  the 
concentration  of  the  parabromacetanilide,  while  the  other 
symbols  have  the  same  meaning  as  before. 

If  now  the  undissociated  salt  is  the  substance  undergoing 
rearrangement,  we  have 


As  discussed  above,  however,  we  can  substitute  for  Csaltund 
in  (3)  the  corresponding  value  in  (2)  and  we  then  get 


-3T       —      Jr  --  ~—     ~a 
Baffin  -ft-  a/ 

K(Chal  —  x)(CSr—x)CH.  (4) 

When  Chal,  CBr  and   CH  are  in  equivalent  concentrations, 
A,  equation  (4)  becomes 

=    K(.A-*)(.A-*)A    or  t  =K,       (5) 


whereas  if  only  the  concentrations  of  the  acetylchloramino- 
benzene  and  of  the  bromide  ions  were  to  be  considered  the 
well-known  equation  by  the  second  order  reaction, 


would  hold.  We  have  therefore  a  method  of  testing  the  ques- 
tion whether  the  undissociated  salt  formed  by  the  union  of 
the  hydrobromic  acid  with  the  acetylchloraminobenzene  is 
the  substance  rearranging  according  to  equation  (5).  By 
simply  varying  the  value  of  A ,  we  can  see  if  a  constant  value 
for  K  is  obtained.  We  must,  however,  expect  some  decrease 
in  the  value  of  K  with  increase  in  the  value  of  A  for  the  fol- 
lowing reasons:  The  A  in  equation  (5)  is  substituted  for 
(Chat — y)  or  (CBr — y)  in  equation  (i).  When  y  is  very  small 
the  error  involved  in  this  substitution  is  small.  Since  y  in- 
creases more  rapidly  than  A  it  is  evident  that  the  error  becomes 


25 

larger  with  increase  in  A,  and  since  A2  occurs  in  the  denom- 
inator in  equation  (5)  the  error  is  still  more  magnified.  In- 
stead of  A2  in  equation  (5)  we  should  have  (A — y)2,  the  value 
of  which  is  not  known.  Since  then  A2  is  larger  than  (A — y)2 
and  occurs  in  the  denominator  the  value  of  K  should  decrease 
with  increase  in  the  value  of  A. 

Since  A2  is  the  function  used  in  equation  (5),  even  a  small 
error  involved  in  the  use  of  A  instead  of  (A — y)  becomes 
magnified  in  A2.  If  (A — y)  equals  0.9  A,  the  value  of  K  de- 
rived from  equation  (5)  is  20  per  cent  less  than  it  should  be, 
whereas  if  (A — y)  equals  o .  6  A  the  value  of  K  is  only  one-third 
as  large  as  it  should  be.  This  fact  then  accounts  to  some  ex- 
tent for  the  decrease  in  the  value  of  K  in  Tables  I.  and  IX.  in- 
clusive. The  results  of  all  the  work  on  the  rearrangements 
by  hydrochloric  acid  and  hydrobromic  acid  makes  it  very  prob- 
able that  the  above  explanation  of  the  cause  of  the  rearrange- 
ment is  essentially  correct.  It  is  probable,  however,  that 
there  are  other  conditions  not  considered  at  all  in  the  above 
equations  which  help  to  cause  a  decrease  in  the  value  of  K  in 
Tables  I.  to  IX.,  inclusive,  and  these  are  now  the  subject  of 
investigation. 

The  experiments  in  Tables  I.  to  IX.  were  carried  out  in  the 
following  manner  in  a  dark  room.  From  0.2  gram  to  2.2  grams 
acetylchloraminobenzene  were  put  into  a  dark  colored  bottle 
holding  something  more  than  600  cc.  The  solid  was  then  dis- 
solved in  60  cc.  glacial  acetic  acid  and  afterwards  540  cc.  water 
were  added.  The  contents  of  the  bottle  were  shaken  up 
thoroughly  and  placed  in  a  bath  of  melting  ice.  When  the 
temperature  had  become  constant,  100  cc.  were  withdrawn 
in  a  pipette  and  quickly  transferred  to  a  beaker  containing 
i.o— 2.0  grams  of  potassium  iodide  in  10—20  cc.  of  water.  The 
iodine  liberated  by  the  unchanged  acetylhalogenaminobenzene 
derivative  was  titrated  with  standard  sodium  thiosulphate. 
From  this  it  was  possible  to  calculate  the  necessary  amount 
of  standard  hydrobromic  acid  to  be  added  to  the  remaining 
500  cc.  of  solution  to  make  unimolecular  equivalents.  The 
time  was  noted  when  this  acid  was  added;  100  cc.  were  with- 
drawn in  a  pipette  from  time  to  time,  added  to  the  potassium 


26 

iodide  solution,  and  the  iodine  titrated  against  sodium  thio- 
sulphate  solution  as  above.  The  results  gave  no  constant 
at  all  for  a  monomolecular  equation,  but  a  very  fair  one 
for  the  bimolecular  equation.  The  time,  T,  is  expressed  in 
minutes  in  all  of  the  following  tables.  In  calculating  the  re- 
sults the  necessary  correction  for  the  change  in  volume  by  the 
addition  of  the  acid  was  made.  The  hydrochloric  acid  libera- 
ted during  the  reaction  acts  so  slowly,  in  comparison  with  the 
hydrobromic  acid,  upon  the  acetylchloraminobenzene  that  this 
factor  is  not  considered  in  the  above  equations. 

In  Tables  I.  to  IX.  inclusive  the  value  K  is  calculated  from 
AK  on  the  basis  of  number  of  cc.  thiosulphate  solution  used. 
Kf  is  calculated  from  AK  on  the  basis  of  the  number  of  gram 
molecules  per  liter  of  acetylchloraminobenzene. 

In  Tables  X.  to  XIV.  inclusive,  approximately  2.0  grams  of 
acetylchloraminobenzene  derivative  were  dissolved  in  the 
same  volume  of  solvent  used  above.  In  these  tables  the  value 
of  K  is  calculated  from  that  of  A  K  on  the  basis  that  the  quan- 
tity of  acetylchloraminobenzene  derivative  present  is  equiva- 
lent to  20  cc.  thiosulphate  solution.  The  values  0.255,  0.260, 
and  0.275  of  K  for  acetylchloraminobenzene  at  2°,  4°  and  5° 
agree  very  closely. 


Table  I. 

0.2  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  540  cc.  water  at  3°;  1.16  cc.  of  1.05  N  HBr  (i  mol.) 
added. 


o  5.31  ...... 

21.66  4.32  0.0106 

46.16  3-54  0.0108 

78.16  2.82  0.0113 

114.5  2-28  0.0116 

157.16  1.90  0.0114 


Average,     o.oin 
K,     0.00039  K't     0.13 


27 

Table  II. 

0.4  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 

acid  and  540  cc.  water  at  3°;  1.91  cc.  of  1.05  N  HBr  (i  mol.) 
added. 

t.                                                Na2S2O3.  A2K. 

0  8.69  

1  .o                              8.53  0.0188 
3.66                            8.10  0.0199 

16.0                               6.45  0.0217 

4O.66                                         4.58  O.O22O 

95.33                       2.70  0.0232 

Average,  0.0211 
K,    0.00028                   K',    0.095 

Table  III. 

0.6  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  540  cc.  water  at  3°;  2.79  cc.  of  1.05  N  HBr  (i  mol.) 
added. 

t.                                               Na2S208.  KA*. 

o                                12.69  

11.25                                          8.92  0.0376 

18.66                             7.40  0.0382 

36.33                             5.23  0.0392 

54-5                               4-02  0.0395 

76.25                             3.16  0.0395 

Average,  0.0388 
Kj    0.00024                   K',    0.081 

Table  IV. 

0.8  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  540  cc.  water  at  3°;  3.72  cc.  of  1.05  N  HBr  (i  mol.) 
added. 

t.                                                  Na2S2O8.  KA2. 

O                                                   16.88  

3.08                                          14.41  0.0556 

8.16  11.55  0.0565 

16.66  8.70  0.0564 

34-33  5.73  0.0566 

62.8  3.60  0.0587 

Average,  0.0568 
K,    0.00019                    K'y    0.067 


28 


Table  V. 

i.i  grams  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  540  cc.  water  at  3°;  5.18  cc.  of  1.094  N  HBr  (i  mol.) 
added. 


t. 

o 

3 

11.66 
20.25 

44.5 
128.5 


K,     0.00017 


24.43 

18.90 

H-37 

8.06 

4.25 
1.32 


Table  VI. 


Average, 
,    0.055 


KA«. 

0.0975 
0.0984 

O.IOO 

0.106 
(0.136) 

O.IOO 


1.6  grams  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  540  cc.  water  at  3°;  7.84  cc.  of  1.094  N  HBr  (i  mol.) 
added. 


/. 
o 
1. 08 

IO 

23.5 

41.16 


K,    0.00015 


36.78 

30.10 

22.00 

12.73 

6.39 

3.80 

Average, 
K',    0.051 

Table  VII. 


KA2. 

0.205 
0.218 
0.189 
O.2O2 
O.2IO 

0.205 


2.2  grams  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  540  cc.  water  at  3°;  10.52  cc.  of  1.094  N  HBr  (i  mol.) 
added. 


o 

0.92 

2.58 

4.66 

11.16 

21.66 


K,     0.00014 


T7  •  • 
36.46 
26.22 

18.79 
9.96 
5-80 

(0.378) 
0.338 
0.347 
0.352 
0.344 

K't 

Average, 
0.048 

0.345 

Table  VIII. 

i.o  gram  acetylchloraminobenzene  (3  mols.)  in  60  cc.  glacial 
acetic  acid  and  540  cc.  water  at  3°;  1.52  cc.  of  1.094  N  HBr 
(i  mol.)  added. 

/.  NaaS,0,.  J-log?^g=K(A-B)B. 


0  21.62  

1  18.80  0.015 
30  16.27  0.015 
60  14.82  0.015 

150  13.93                            

36i  13.94                            

1440  13.32 

Average,     0.015 

Kt  0.00014 


Table  IX. 

0.333   gram   acetylchloraminobenzene    (i  mol.)   in   60   cc. 

glacial  acetic  acid  and  540  cc.  water  at  3°;  4.53  cc.  of  1.094 
N|HBr  (3  mols.)  added. 

*•                                                 NazSjOs.               r  10g  A(B  — *)  =  K(A~  B)B. 
O  7.14  

2.16                            6.21  (0.029) 

6.25                                        4.65  0.021 

14                                                2.82  0.022 

27.75                                        1-26  0.021 

59                                                0-20  ^^. 

2O2                                                   O.OO  .  .  .  +.••.; 

Average,     0.021 
K,    0.00021 


30 

Table  X. 

0.8  gram  acetylchloraminobenzene  in  30  cc.  glacial  acetic 
acid  and  265  cc.  water  at  2°;  3.81  cc.  (i  mol.)  of  1.05  N  HBr 
added. 

/.  Na2Sa08.  AK. 

o  17-31  

i.o  14.01  0.236 

3.75  9.87  0.196 

14.75  4-37  0.203 

25.25  2.37  0.252 

48 . 50  i .  56  o .  208 

Average,    o .  22 
K,    0.255 

Table  XL 

0.8  gram  acetylchloraminobenzene  in  30  cc.  glacial  acetic 
acid  and  2 .70  cc.  water  at  4°;  4.61  cc.  of  1.05  N  HBr  (  i  mol.) 
added. 

t.  Na2S203.  AK. 

o  20 . 60  

I. 12  16.57 

2.87  11.56 

7.63  6.44 

15.50  3.30 

33.75  2.18 

Average,    0.27 
K,    0.26 

Table  XII. 

0.8  gram  acetylchloraminobenzene  in  30  cc.  glacial  acetic 
acid  and  278  cc.  water  at  5°;  4.39  cc.  of  1.05  N  HBr  (  i  mol.) 
added. 


t.  NajSaOs.  AK. 

o  19.62  

0.87  15.10  (0.34) 

3.25  10.28  0.28 

8.37  6.01  0.27 

16.00  3.72  0.27 

32.00  2.18  0.25 

Average,     0.27 

K,  0.275 


The  reaction  between  hydrobromic  acid  and  paratolyl- 
acetylnitrogenchloride  was  studied  and  the  results  are  given 
in  the  following  tables.  Conditions  were  the  same  as  with 
the  acetylchloraminobenzene.  In  each  case  the  constant  was 
calculated  from  the  bimolecular  equation.  The  two  sets  of 
constants  agree  very  well  and  show  the  rearrangement  of  the 
paratolylacetylnitrogenchloride  by  one  molecular  quantity  of 
hydrobromic  acid  to  be  only  about  one-third  as  rapid  as  that 
of  the  acetylchloraminobenzene. 


Table  XIII. 

0.7  gram  paratolylacetylnitrogenchloride  in  30  cc.  glacial 
acetic  acid  and  270  cc.  water  at  5°;  2.65  cc.  of  1.05  N  HBr 
(  i  mol.)  added. 


t.  NajSaOs.  AK. 

o  H-94  .... 

3-00  10.15  0.059 

8.25  8.02  0.059 

18.50  5.77  0.058 

36.50  4-38  (0.047) 

Average,    0.058 

K,  0.098 


Table  XIV. 

0.7  gram  paratolylacetylnitrogenchloride  in  30  cc.  glacial 
acetic  acid  and  270  cc.  water  at  5°;  2.69  cc.  of  1.055  N  HBr 
(i  mol.)  added. 

/.                                                Na2Sj03.                                           AK. 
O  12 .09  

1.50  11.06 

5-00  9.37 

18.00  5.89 

30.00  4.47 

50.00  3.30 

Average,    0.058 
K,    0.098 


K  32 

Rearrangement  Experiments  with  Hydrochloric  Acid. 

The  constant  in  each  case  is  calculated  from  the  monomo- 

i  A 

lecular    equation  (6)  -r  log  *  =  KC^.     In  the  following 

series  of  experiments  with  acetylchloraminobenzene  and  hydro- 
chloric acid,  the  acid  was  added  in  amounts  equivalent  to  those 
of  Blanksma1  when  he  used  10,  15,  20,  etc.,  cc.  of  28.67  Per  cent 
hydrochloric  acid  to  500  cc.  of  solution.  I  used  the  same 
proportion  of  a  different  strength  of  acid  to  250  cc.  of  solution. 
Ten  cc.  of  28.67  Per  cent  hydrochloric  acid  to  500  cc.  solution 
are  taken  as  the  standard  and  will  be  designated  as  M  amount 
of  acid ;  others  will  be  2M,  3M,  etc.  Corrections  were  applied 
for  the  difference  in  volume  when  the  acid  was  added  to  the 
standard  solution  of  the  acetylchloraminobenzene  derivative 
instead  of  making  the  entire  solution  standard  as  Blanksma 
did.  Tables  XV.  to  XVIII.,  inclusive,  show  that  the  velocity 
constant  decreases  with  increasing  per  cent  of  water. 

Tables  XIX.  and  XX.  show  the  relative  reaction  velocities 
at  4°  and  25°. 

Tables  XXI.  to  XXVII.,  inclusive,  show  the  change  of  veloc- 
ity of  transformation  with  change  in  concentration  of  hydro- 
chloric acid  in  20  per  cent  acetic  acid  solution  at  25°. 

Tables  XXVIII.  to  XXXIV.,  inclusive,  show  the  change 
of  velocity  of  transformation  with  change  in  concentration  of 
hydrochloric  acid  in  30  per  cent  acetic  acid  solution  at  25°. 

Tables  XXXV.  and  XXXVI.  are  a  general  resume"  of  Tables 
XXI.  to  XXXIV.,  inclusive,  and  of  Blanksma's  work,  showing 
that  the  velocity  of  the  transformation  increases  as  the  square 
of  the  concentration  of  the  hydrochloric  acid.  The  change  in 
percentage  of  ionization  of  the  hydrochloric  acid  with  the  small 
changes  in  dilution  used  in  these  experiments  is  small  and  hardly 
affects  the  values  of  the  constant. 

Tables  XXXVII.  to  XLIIL,  inclusive,  are  a  miscellaneous 
set  showing  the  velocity  of  transformation  of  acetylchlor- 
aminobenzene by  sulphuric  acid  and  by  acetic  acid,  and  the 
velocity  of  transformation  of  paratolylacetylnitrogenchloride 
by  hydrochloric  acid. 

iLoc.cit. 


33 

The  investigation  will  be  continued. 

Table  XV. 

2.0  grams  acetylchloraminobenzene  in  180  cc.  glacial  acetic 
acid  and  120  cc.  water  at  25°;  8.58  cc.  of  5.49  N  HC1  (1.2  mol.) 
added. 

t.  Na2S203.  K. 

O  43-19  ..... 

5  27.32 

10  16.32 

15  9-43 

20  5.56 

30  2.02 

Average,     0.032 
Table  XVI. 

i.o  gram  acetylchloraminobenzene  dissolved  in  120  cc.  glacial 
acetic  acid  and  180  cc.  water  at  25°;  7.16  cc.  of  5.49  N  HC1 
(i  mol.)  added. 

t.  NajSaOa.  K. 

o  18.65  ..... 

15  15.38  0.0057 

30  12.68  0.0057 

60  8.84  0.0057 

75  7.24  0.0055 

95  5-82  0.0055 

120  4.32  0.0054 

160  2.62  0.0054 

Average,     0.0055 
Table  XVII. 

i.o  gram  acetylchloraminobenzene  in  90  cc.  glacial  acetic 
acid  and  210  cc.  water  at  25°;  7.16  cc.  of  5.49  N  HC1  (i  mol.) 
added. 


t.  NaaSaOa.                                                K. 

O  18.68  ...... 

60  n.oo  0.0038 

95  8.25  0.0037 

I2O  6.83  O.OO36 

150  5.37  0.0036 

180  4.46  0.0035 

Average,    0.0036 


34        '::   ,  :-;  ' 

Table  XVIII. 

i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  240  cc.  water  at  25°;  7.16  cc.  of  5.49  N  HC1  (i  mol.) 
added. 

t.                                            NaaSsOg.  K. 

o                             17-92  

63                                            12.63  0.0024 

120                                  9 .50  0.0023 

ISO                                                7-21  0.0022 

240                                                5.63  0.0021 

300                                 4 . 48  o . 0020     . 


Average,     0.0022 

The  two  following  tables  are  given  to  show  the  temperature 
coefficient  for  the  reaction  at  4°  and  at  25°.  The  velocity  of 
transformation  is  about  3.5  times  as  great  at  25°  as  at  4°. 

Table  XIX. 

i.io  grams  acetylchloraminobenzene  in  30  cc.  glacial  acetic 
acid  and  270  cc.  water  at  4°;  1.5  cc.  of  6.59  N  HC1  added. 

t.  Na2Sa08.  K. 

o  15.60                          

61  15.38  (o.oooio) 

232  15.29  0.000038 

482  15.02  0.000035 

1140  14.50  0.000027 

1663  14.06  0.000027 

Average,     o .  00003  2 
Table  XX. 

i.o  gram  acetylchloraminobenzene  in  30  cc.  glacial  acetic 
acid  and  270  cc.  water  at  25°;  1.5  cc.  of  6.59  N  HC1  added. 

t.  Na2S208.  K. 

o  16.17  

I2O  15.62  O.OOOI2 

270  I5.OI  O.OOOI2 

438  14.34  0.00012 

600  13-94  o.ooon 

1280  13.01  0.00007 

1783  10.62  o.oooio 

Average,    o.ooon 


35 

The  following  sets  of  tables  show  the  variation  in  the  ve- 
locity constants  with  variations  in  the  concentration  of  the 
hydrochloric  acid  when  the  concentration  of  the  acetylchlor- 
aminobenzene  is  approximately  the  same  in  all  the  experiments. 


Table  XXL 

i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 

acid  and  237.44  cc.  water  at  25°;  2.56  cc.  of  7.68  N  HC1 
(o.5mol.)  added. 

*.  Na2S203.  K. 

O.  13-44  

60  12.30  0.00064 

150  10.72  0.00065 

240  9.27  O.OOO67 

390  7-44  0.00066 

580  6.10  0.00060 

Average,  o .  00064 


Table  XXII. 

i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  240  cc.  water  at  25°;  7.16  cc.  of  5.49  N  HC1  (i  mol.) 
added. 


/.  NasSaOs.  K. 

o  17.92 

63  12.63 

120  9.50 

180  7.21 

240  5.63 

300  4.48 

Average,    0.0022 


36 

Table  XXIII. 

i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  240  cc.  water  at  25°  ;  10.74  cc-  of  5.49  N  HC1  (1.5  mol.) 
added. 


t.                                       NaaSjjOs.  K. 

O                                         22.12  ...... 

30                 17.31  (0.0036) 

60                 12.34  0.0042 

90                  9.17  0.0043 

120                               6.88  0.0042 

150                          5.24  0.0041 

180                              4-14  0.0041 

Average,  0.0041 

Table  XXIV. 

i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  240  cc.  water  at  25°  ;  14.49  cc.  of  5.45  N  HC1  (  2  mol.) 
added. 

t.                                        Na2S208.  K. 

o                             21.05  ...... 

3O                                           13.66  O.OO67 

45                               10.78  0.0068 

6O                                             8.39  O.OO7I 

75             6.62  0.0072 

90             5-34  0.0068 

Average,  0.0069 

Table  XXV. 

i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  221.86  cc.  water  at  25°;  18.16  cc.  of  5.45  N  HC1 
(2.5  mol.)  added. 

t.                                          NasSaOj.  K. 

O                                        22.26  ...... 

10  16.38 

20  12.30 

30  9  •  H 

40  6.94 

50  5-30 

Average,  0.0128 


37 
Table  XXVI. 

i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  218.2  cc.  water  at  25° ;  21.80  cc.  of  5.45  N  HC1  (3  mol.) 
added. 

t.  NaaSa08.  K. 

o  22.52  

5  17.81  0.0204 
10           14.08  0.0204 

15  11.23  0.0202 

25  7-l6  0.0199 

40  3-74  0.0195 

Average,     0.0201 

Table  XXVII. 

i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  213.4  cc.  water  at  25°;  26.6  cc.  of  7.68  N  HC1  (5  mol.) 
added. 

t.  Na2S808.  K. 

o  16.13  

3  9.96  0.0698 

6  6.36  0.0674 
9  3-93  0.0681 

15  1.68  0.0655 

21  1.82  0.0616 

Average,    0.0663 

Table  XXVIII. 

i.o  gram  acetylchloraminobenzene  in  90  cc.  glacial  acetic 
acid  and  207.44  cc.  water  at  25°;  2.56  cc.  of  7.68  N  HC1 
(0.5  mol.)  added. 

/.  Na2Sa08.  K. 

o  15.20  

60  12.22  (O.00l6) 

I2O  H-49  O.OOIOI 

210  9.25  0.00102 

330  6.92  0.00103 

480  4.76  O.OOIO5 

Average,    0.00103 


38 
Table  XXIX. 

i.o  gram  acetylchloraminobenzene  in  90  cc.  glacial  acetic 
acid  and  210  cc.  water  at  25°;  7.16  cc.  of  5.49  N  HC1  (i  mol.) 
added. 

t.  Na2S203.  K. 

O  18.68  ...... 

60  ii. oo  0.0038 

95  8.25  0.0037 

120  6.83  0.0036 

150  5.37  0.0036 

180  4.46  0.0035 

Average,     0.0036 

Table  XXX. 

i.o  gram  acetylchloraminobenzene  in  90  cc.  glacial  acetic 

°;   7.68   cc.  of  7.68  N  HC1 


acid  and  202.32  cc. 

water  at   25' 

(1.5   mol.)  added. 

t. 

NaaSjjOs. 

0 

18.15 

15 

13.42 

30 

9-99 

45 

7.42 

60 

5-52 

75 

4.18 

0.0087 
0.0086 
0.0087 
0.0086 
0.0085 

Average,     0.0086 

Table  XXXI. 

i.o  gram  acetylchloraminobenzene  in  90  cc.  glacial  acetic 
acid  and  195.47  cc.  water  at  25° ;  14.53  cc.  of  5.45  N  HC1  (2  mol.) 
added. 

t.  Na2S208.  K. 

o  22.72 

10  16.23  0.0146 

20  11-57  0.0147 

3O  8.22  O.OI47 

55  3-6i  0.0145 

80  1.73  0.0148 


Average,     0.0146 


39 
Table  XXXII. 

i.o  gram  acetylchloraminobenzene  in  90  cc.   glacial  acetic 

acid  and  197.2  cc.  water  at  25°;  12.80  cc.  of  7.68  N  HC1  (2.5 
mol.)  added. 

t.                                              Na2S2O3.  K. 

o                              17.10  

5  13.02  0.0277 

10  9.97  0.0234 

15  7.72  0.0230 

20                   5.90  0.0231 

30           3.60  0.0226 


Average,     0.024 

Table  XXXIIL 

i.o  gram  acetylchloraminobenzene  in  90  cc.  glacial  acetic 
acid  and  194.64  cc.  water  at  25°;  15.36  cc.  of  7.68  N  HC1 
(3  mol.)  added. 

t.  NasS208.  K. 

o  17-19  

3  J3-90  0.0307 

7  10-34  0.0315 

11  7.78  0.0313 
15             5.8o  0.0315 
19             4.32  0.0316 

Average,     0.0313 

Table  XXXIV. 

i.o  gram  acetylchloraminobenzene  in  90  cc.  glacial  acetic 
acid  and  184.4  cc-  water  at  25°;  25.6 cc.  of  7.68  N  HC1  (5  mol.) 
added. 

t.  NaiS2O3.  K. 

o  17.95  

2  10.42 

4  6.16 

6  3-73 

8  2.29 

12  0.92 

Average,    0.114 


40 

Summary. 

The  two  following  tables  give  a  summary  of  the  preceding 
ones  and  of  Blanksma's  work.  Ordinary  logarithms  were 
used  instead  of  the  natural  system.  The  list  under  "glacial 
acetic  acid"  gives  the  volume  per  cent  of  acetic  acid  used  in 
the  solution.  The  table  under  HC1  gives  the  concentrations 
of  the  hydrochloric  acid,  calculated  as  explained  above.  The 
constants  in  parenthesis  are  the  values  calculated  from  the 
average  constant.  It  will  be  noticed  that  the  agreement  be- 
tween the  calculated  and  found  values  is  very  good.  Blanks- 
ma's  table  shows  that  an  increase  of  10  per  cent  in  the  concen- 
tration of  the  acetic  acid  causes  approximately  a  doubling 
of  the  constants. 


•8  * 

ft  >-» 

8  8 


8  I 

"8 « 

8  S 


o  o  CD  o 


VO  O  Cn  ON 
OOCo  ONCn 


O    O  'p*  p  'p'  O 

Oi  Cn    §    O    8    O    ^ 

W  Cn  Oi  OJ    N>    K)    ' 

O\\O   ON  M   W 


So  b 

W     M  M 

4»-  W  C/a  K> 

K)  VO  W  0 


0  O    O    O 

b  b  b  b 

Oi  Oi    M    M 

^.   M  \O   O 

0001  vO    M 


O  O  O  O 

b  M  b  b  g 

vO  M  Cn  ON  S 
^1  Co  Co  ON 
>— x   vO  Co 


42 

Table  XXXVI.  (Blanksma's). 
HC1. 


Glacial  acetic  acid. 

IO  CC. 

15  cc. 

20  CC. 

25  cc. 

20  per  cent 

0.00218 

0.00419 

O.OO8I4 

0.0104 

30       " 

0.00364 

0.00802 

0.0137 

0.0198 

40       " 

0.00676 

0.0144 

0.0253 

50       " 

0.0155 

0.0309 

60 

0.036 

Table  XXXVII. 

The  effect  of  the  suppression  of  ionization  was  studied. 
i.o  gram  acetylchloraminobenzene  in  60  cc.  glacial  acetic 
acid  and  227.2  cc.  water  at  25°;  4.4  grams  of  KC1  (10  mol.) 
and  12.80  cc.  of  7.68  N  HC1  (2.5  mol.)  added.  The  effect 
was  to  increase  greatly  the  velocity  of  reaction. 

t.  NaaS2O8.  K. 

o  16.83  

10  10.84  0.0191 

20  6.88  0.0194 

30  4.50  0.0191 

40  •          2.92  0.0190 

r  50  1.84  0.0192 


Average,    0.0192 


Table  XXXVIII. 

KC1  alone  causes  very  little  change,  i  gram  acetylchlor- 
aminobenzene in  60  cc.  glacial  acetic  acid  and  240  cc.  water  at 
25°;  4.4  grams  KC1  (10  mol.)  added. 

t.  Na2Sa08.  K. 

o  16.02  

30  15.74  (0.00025) 

9O  15.64  O.OOOI2 

»  185  I5.O8  O.OOOI4 

300  14.65  0.00013 

420  14.00  0.00014 

Average,    o .  oooi  3 


43 
Table  XXXIX. 

Glacial  acetic  acid  alone  causes  very  little  rearrangement; 

i  gram  acetylchloraminobenzene  in  90  cc.  glacial  acetic  acid 
and  210  cc.  water  at  25°. 

t.                                      Na2S2O8.  K. 

o                          16.70  

120                16.63  0.000015 

360                16.54  0.000012 

1380                16.45  0.0000048 

IQOO                I6.4I  O.OOOOO40 

2935                16.37  0.0000029 

Table  XL. 

Rearrangement  experiment  with  sulphuric  acid;  i.i  grams 
acetylchloraminobenzene  in  30  cc.  glacial  acetic  acid  and  270  cc. 
water  at  4°;  5.3  cc.  of  N  H2SO4  added. 

t,                                       Na2S2O8.  K. 

o                         21.37  

4                           20.82  0.0028 

36                           20.75  0.00036 

103                            19.93  0.00029 

960                          17.01  o.oooio 

4115                          15.88  0.000031 

8190                          13.26  0.000025 


Table  XLI. 

0.7  gram  paratolylacetylnitrogenchloride  in  30  cc.  glacial 
acetic  acid  and  270  cc.  water  at  3°;  2.50  cc.  of  6.59  N  HC1 
(5  mol.)  added. 

t.  Na2S20,.  K. 

o  14-19  

28.12  13.63  0.00062 

58.50  13.10  0.00059 

120.75  12. 18  0.00055 

289.87  9.47  0.00061 

420.00  7.56  0.00065 

Average,     o .  0006 1 


44 
Table  XLIL 

0.7  gram  paratolylacetylnitrogenchloride  in  30  cc.  glacial 
acetic  acid  and  260  cc.  water  at  3.5°;  7.82  cc.  of  6.59  N  HC1 
(20  mol.)  added. 

K. 


o  11.25  ........ 

16.5  11.05  (0.00092) 

45  10.96  0.00025 

90  10.67  0.00025 

150  10.19  0.00028 

300  7.96  0.00030 

Average,     o  .  0002  7 
Table  XLIII. 

0.6  gram  paratolylacetylnitrogenchloride  in  30  cc.  glacial 
acetic  acid  and  260  cc.  water  at  3°;  7.82  cc.  of  5.49  N  HC1 
(20  mol.)  added. 

K. 


o  9.32  

30         9.05        (0.00043) 

60  8.98  0.00027 

90  8.80  0.00028 

150  8.42  0.00029 

360  7.14  0.00032 

Average,     0.00029 

While  Tables  XLII.  and  XLIII.  agree  very  well,  they  do  not 
harmonize  with  Table  XLI.  and  the  general  results  obtained 
above.  In  Tables  XLL,  XLII.  and  XLIII.  the  concentration 
of  the  hydrochloric  acid  used  was  calculated  from  the  concen- 
tration of  the  paratolylacetylnitrogenchloride. 

GENERAL    DISCUSSION    OF    THE    HYDROLYSIS   OF    AMIDES,    CANE- 
SUGAR,  OXIMES  AND  ESTERS. 

In  the  hydrolysis  of  esters,  cane-sugar,  amides,  amidines, 
nitriles,  oximes  and  related  compounds  we  are  dealing  with 
weak  bases  in  the  presence  of  acids  and  water.  Many  salts 
of  these  weak  bases,  amides,  nitriles,  esters  and  oximes,  have 
been  isolated  and  studied.  The  affinity  constant  for  acet- 


45 

amide,1  for  instance,  is  3  X  io~~15  at  25°,  and  that  for  pro- 
pionitrile  at  the  same  temperature  is  1.8  X  io~15.  The  work 
of  Collie  and  Tickle,2  Baeyer  and  Villiger,3  Werner,4  Briihl,5 
Archibald  and  Mclntosh,6  Walden,7  van't  Hoff8  and  many 
others  leaves  no  doubt  that  esters,  ketones  alcohols,  sugars, 
ethers,  and  organic  acids  are  weak  bases  and  form  tetravalent 
oxygen  salts  which  are  derivatives  of  the  hypothetical  ox- 
onium  hydroxide,  H3OOH.  The  work  of  Sackur,9  Kablu- 
koff,10  Coehn,11  Walden,12  Baeyer  and  Villiger,  Collie  and 
Tickle,  Archibald  and  Mclntosh  and  Walker13  have  shown 
conclusively  that  these  salts  are  electrolytes,  in  which  the 
tetravalent  oxygen  compound  probably  forms  part  of  the  cathion. 
The  affinity  constant  of  dimethylpyrone  as  a  base,  for  instance, 
was  found  to  be  about  2.4  X  io~14.  In  cane-sugar,  ethers, 
and  similar  compounds  we  have  a  COC  linkage,  which  can 
H 

form  salts,  COC.     There  is  plenty  of  evidence  to  show  that 

I 
Cl 

all  these  compounds  have  both  basic  and  acid  properties. 

Now  the  work  of  Arrhenius,14  of  Walker15  and  of  Shields16 
has  shown  that  when  these  weak  bases  are  treated  with  acids 
a  small  amount  of  salt  is  formed  according  to  the  following 
equation  : 

(Csu&  -  X)    X   Cff      =      KhydCsaltdis       =       JT^Csaltdist  (0 


1  Z.  physik.  Chetn.,  4,  319.     Ahren's  Sammlung,  Abegg,  8,  183. 

f  J.  Chem.  Soc.,  75,  710. 

8  Ber.  d.  chem.  Ges.,  34,  2692;  35,  1201. 

4  Ann.  Chem.  (Liebig),  322,  296.    Ber.  d.  chem.  Ges.,  34,  3300. 

6  Ibid.,  28,  2847,  2866.     Z.  physik.  Chem.,  18,  514. 

6  Ibid.,  55,  129.     Phil.  Trans.,  205,  99.     J.  Chem.  Soc.,  85,  919. 

7  Ber.  d.  chem  Ges.,  34,  4185. 

8  Ansichten  uber  die  Organische  Chemie,  I  Theil,  p.  62,  fol. 

9  Ber.  d.  chem.  Ges.,  35,  1242. 
10  Z.  physik.  Chem.,  4,  429. 

»«  Ber.  d.  chem.  Ges.,  35,  2673. 

12  Ibid.,  34,  4185;  35,  1764. 

"  J.  Chem.  Soc.,  85,  1098.     Ber.  d.  chem.  Ges.,  34,  4115. 

14  Z.  physik.  Chem..  5,  1;  13,  407. 

«  Ibid.,  4,  319;  32.  137;  J.  Chem.  Soc.,  77,  5. 

w  Z.  physik.  Chem.,  12,  167. 


46 

in  which,  C5ub  is  the  original  concentration  of  the  base  in  gram 
molecules  per  liter,  oc  the  amount  of  base  transformed  into 
the  other  products  at  any  moment,  (Csub  —  x)  the  concen- 
tration of  the  base  at  any  moment,  CH  that  of  the  hydrogen 
ions,  Csaltdis  that  of  the  dissociated  portion  of  the  salt, 
practically  all  ionized,  Khyd  the  hydrolysis  constant,  Kb  the 
affinity  constant  of  the  base  and  Kw  the  ion  product  for  water 
at  the  given  temperature.  But  the  amount  of  salt,  Csalidis, 
present  in  such  cases  is  extremely  small  and  for  (Csub  —  x) 
and  Cff  we  may  substitute,  without  appreciable  error, 
the  values  they  would  have  if  no  salt  were  formed.  In  those 
cases  in  which  Csaltdis  is  large  this  cannot  be  done,  but  the 
concentrations  of  each  substance  can  be  determined  from  (i). 

It  is  the  opinion  of  a  large  number  of  chemists  that  the 
above  salts  are  intermediate  compounds  in  the  catalytic  trans- 
formations spoken  of,  and  that  such  catalytic  reactions  are 
brought  about  solely  because  of,  and  through,  the  formation 
of  such  intermediate  compounds. 

The  work  of  Remsen  and  Reid1  on  the  hydrolysis  of  amides 
by  acids,  and  of  Acree  and  Johnson2  from  theoretical  grounds, 
indicated  an  intermediate  formation  of  an  amide  salt,  the 
cathion  of  which  reacts  with  water  and  forms  an  acid  and  the 
ammonium  ion,  just  as  the  urazole  ion  reacts  with  the  neutral 
ethyl  iodide. 


CH3CONH2  4.  H  +  Cl  +  H2O 

CH3CONH3  +  H2O  +  Cl     »*- 

CH3COOH  +  NH4  +  Cl. 

This  idea  is  fully  verified  by  the  work  of  Mr.  Sidney 
Nirdlinger  in  this  laboratory  and  by  all  the  data  of  Ost- 
wald.  Julius  Stieglitz3  has  further  verified  this  by  work 
on  the  hydrolysis  of  imido  esters  in  the  presence  of  acids, 
in  that  he  showed  that  the  imido  ester  cathion  is  hydrolyzed: 

i  Am.  Chem.  J.,  21,  281;  Reid:  Ibid.,  24,  397. 

»/&*<*.,  37,  410. 

>  Congress  of  Arts  and  Science,  St.  Louis,  1904,  4,  276. 


47 

C6H5C(NH)OC2H5  +  H  4  Cl  4  H2O 

C6H5C(NH2)OC2H5  4  H20  +  Cl 

CeH6COOC2H5  4-  NH4  4-  Cl. 

Lapworth1  and  then  Bredig  and  Stern2  showed  that  cyan- 
ides act  catalytically  in  causing  such  condensations  as  the 
formation  of  benzoin  from  benzaldehyde,  solely  because  the 
cyanide  ion  unites  with  benzaldehyde  and  forms  a  complex 
anion  which  reacts  with  benzaldehyde  and  yields  benzoin  and 
a  cyanide  ion. 

2C6H6CHO  +  K  +  CN     ^ 

C6H5CH(CN)O  4  K  4  C6H5CHO    ~+ 

C6H5CHOHCOC8H6  4  K  4  CN. 

Bredig3  and  Euler4  suggested  that  acids  cause  the  catalytic 
inversion  of  cane-sugar  in  water  solutions,  and  of  diazoacetic 
ester  and  other  esters  in  water  because  the  hydrogen  ions 
unite  with  the  weak  bases,  sugar  and  esters,  and  form  salts 
which  are  hydrolyzed  by  the  water. 

(C.HnOB),0  4  H  4  Cl  4-  H20     ^ 

(CeHuOtt)aOH  4  H20  4  Cl    —^ 

2C6H1206  4-  H  4-  Cl. 

Luther  and  Sammet5  have  shown  that  the  equilibrum  be- 
tween iodic  acid,  hydriodic  acid,  iodine  and  water  is  between 
the  hydrogen,  iodide  and  iodate  ions  on  the  one  hand  and 
iodine  and  water  on  the  other  and  can  be  expressed  by  the  equa- 
tion 

1  J.  Chem.  Soc.,  83,  995. 

»  Z.  Elek.  Chem.,  10,  585. 

*Ibid.,  9,  118;  10,  586;  11,  528. 

«  Z.  physik.  Chem.,  36,  405,  663 ;  40,  501 ;  47,  356. 

*  Z.  Elek.  Chem.,  11,  293. 


48 
=     2.8(±o.3)  X 


Finally,  Bredig,  Euler,1  Abegg,2  Goldschmidt,3  Wegscheider,4 
Zengelis,5  Lapworth,6  Kastle,7  Stieglitz,8  and  Acree  and 
Johnson9  have  discussed  the  saponification  of  esters  and  for- 
mation of  esters  from  the  point  of  view  that  intermediate  ions 
are  the  substances  transformed.  Lapworth,  Bredig,  Euler, 
Stieglitz,  and  Acree  and  Johnson  have  believed  that  an  ap- 
plication of  the  mass  law  harmonizes  with  the  idea  that  esters 
may  be  saponified  by  water  in  the  presence  of  acids  because 
of  the  intermediate  formation  of  an  ester  cathion  which  is 
hydrolyzed, 

CH3COOR  +  H  +  Cl  +  H2O     ^ 

CHSCOOR.H  -f  H2O  -f  Cl    •>•*- 

CH3COOH  +  ROH  +  H  +  Cl, 

and  Acree  and  Johnson10  have  shown  from  theoretical  grounds, 
that  the  undissociated  ester  salt  is  not  the  substance  which 
chiefly  is  hydrolyzed. 

If  now,  in  the  catalysis  of  cane-sugar,  esters,  etc.,  we  have, 
in  general,  an  intermediate  salt  formation  and  a  direct  hydrol- 
ysis of  complex  ion,  the  velocity  of  transformation  of  the  cane- 
sugar  must  be  dependent  upon  the  concentrations  of  the  com- 
plex ion  and  the  water,  or 

dCsub  cathion  dx  f    . 

»j  —        j.  R-trans^-' sub  cathion    X.    i-Jf^O  j       \% ) 

»  Z.  physik.  Chem.,  36,  405,  663;  40,  501 ;  47,  356. 

«  Z.  Elek.  Chem.,  10,  185. 

•  Ibid.,  10,  221. 

*Z.  physik.  Chem.,  39,  257;  41,  62. 

•Ber.  d.  chem.  Ges.,  34,  198. 

3  See  Mellor's  "  Chemical  Statics  and  Dynamics,"  1904,  p.  289. 

7  Private  communication.  Am.  Chem.  J. ,  19,  894.    P.  Am.  Assn.  Adv.  Sci.,  47,  238. 

8  Loc.  cit. 

»  Am.  Chem.  J.,  37,  410. 
«>  Loc.  cit. 


49 

in  which  —dCsub  cathion^rdxt  is  the  small  amount  of  Csubcathion 
hydrolyzed  in  the  time  dt,  CH^O  is  the  original  concen- 
tration of  the  water,  and  x  the  amount  of  water  which 
has  been  used  up  in  the  reaction  at  the  time  under  con- 
sideration. The  small  amount  —  dCsttb  cathion  changed  in  dt  is 
exactly  equal  in  gram  equivalents  to  the  small  amount  dx 
of  sugar  and  of  water  changed  in  the  same  time  interval.  We 
may,  therefore,  consider  these  two  equivalent  in  all  of  the 
cases  under  consideration  and  write  dx  for  the  small  amount 
of  substance  transformed  whether  it  be  the  intermediate 
compound  or  the  sugar,  ester,  etc.  The  dx  represents  an  in- 
crease, whereas  —  dCsubcathion  represents  a  decrease;  hence  the 
one  is  the  negative  of  the  other. 

In  the  total  reaction,  expressed  by  equations  (i)  and  (2),  we 
are  dealing  with  two  consecutive  reactions.  The  first  is  a  rever- 
sible reaction  involving  what  may  be  considered,  for  practical 
purposes,  a  bimolecular  and  a  unimolecular  reaction.  The  second 
is  a  practically  non-reversible  bimolecular  reaction.  Now  the 
concentration  of  Csubcathion  at  any  moment  depends  upon 
the  concentrations  of  the  sugar,  hydrogen  ions,  anions,  and 
water,  at  the  moment  and  upon  the  velocities  of  the  first  and 
second  reactions.  Now  the  first  reaction  is  the  neutraliza- 
tion of  a  base  by  an  acid,  and  all  such  reactions  take  place, 
as  a  rule,  immeasurably  rapidly.  The  second  reaction  is 
therefore  very  slow  in  comparison  with  the  first,  and  the  equilib- 
rium expressed  in  equation  (i)  is  never  appreciably  disturbed 
by  the  change  in  the  concentration  of  CsubcatMon  in  reaction  (2). 

It  is  evident  then,  from  (i),  that  we  can  substitute 

kC«rf  —  *)  X  CH 


.w 


Csubcathion  ™  Wjand  we  then  get 
r£     =     Kiran5~L(Csub  —  x}  X  CffX  (Cff^o  —  x).      (3; 


But  this  is  exactly  the  relation  found  experimentally  for  the 
hydrolysis  of  amides,  inversion  of  cane-sugar  and  the  saponi- 
fication  of  esters.  It  is  evident,  then,  that  intermediate  sugar 


50 

cathions,  ester  cathions,  amide  cathions,  etc.,  may  be  the 
substances  chiefly  undergoing  hydrolysis. 

But  Acree  and  Johnson1  have  shown,  further,  that  the  un- 
dissociated  sugar  salt,  ester  salt,  or  amide  salt  is  certainly  not 
the  substance  chiefly  .  undergoing  hydrolysis. 

If  such  were  the  case  the  velocity  of  transformation  of  the 
sugar,  ester  or  amide  would  be  proportional  to  the  concentra- 
tions of  the  undissociated  salt  and  the  water,  or 

desalt  und  &X  -rr  ^  ^/    f  r*  \         f    \ 

salt  und   X    {L-ff2O  -  £/•       LA/ 


at  at 

But  the  undissociated  salt  is  in  equilibrium  with  its  ions  and 

dis   X   Cci      —      Kaffin  CSalt  und>  (5) 


By  substituting  in  (4)  the  value  of  Csaltund  derived  from 
(i)  and  (5)  under  the  same  conditions  discussed  above  for  the 
sugar  cathions,  we  derive 

dx  Kiran5Kb 


su 

al  Baffin  -ft-  a/ 

K(Csub-x)  X  C*H  X  (CH.O  —  X).  (6) 

But  equation  (6)  does  not  correspond  to  the  facts  found  ex- 
perimentally. The  velocity  of  saponification  of  esters,  amides 
and  cane-sugar  is  not  proportional  to  the  square  of  the  concen- 
tration of  the  hydrogen  ions,  but  simply  to  the  concentration. 
Since  in  a  water  solution  of  the  weak  bases,  cane-sugar,  esters 
amides,  oximes  and  acids  there  are  present  (i)  the  free  base, 
that  is,  the  sugar,  ester,  etc.;  (2)  the  undissociated  salt;  and 
(3)  the  dissociated  salt;  one  of  these  three  must  be  the  sub- 
stance hydrolyzed.  Since  the  free  base,  that  is,  the  cane-sugar 
etc.,  and  the  undissociated  salt  are  not  chiefly  concerned  in  the 
hydrolysis,  it  is  evident  that  the  substance  undergoing  hy- 
drolysis must  be  the  complex  cathion  formed  by  the  union  of 
hydrogen  ions  with  cane-sugar,  esters  amides,  oximes,  etc. 
The  equations  worked  out  above  are  not  exact,  but  the  errors 
involved  in  using  them  are  probably  within  the  limits  of  ex- 
periment. An  exact  application  of  the  mass  law  would  lead 

»  Loc.  cit. 


51 

to  very  complex  equations  which  would  hardly  lend  themselves 
to  a  practical  solution  of  the  problem  with  the  data  now  at 
hand. 

We  are  now  in  a  position  to  discuss  the  evidence  bearing  on 
each  of  the  above  catalytic  reactions. 

ON  THE  INVERSION  OF  CANE-SUGAR  IN  AQUEOUS  SOLUTIONS  OF 

ACIDS. 

Ostwald,1  Cohen,2  Smith,3  Wilhelmy,4  Arrhenius,5  Uhrech,6 
Spohr7  and  Trevor8  have  shown  that  aqueous  solutions  of 
cane-sugar  are  hardly  affected  by  pure  water,  but  inversion 
of  the  sugar  takes  place  upon  the  addition  of  acids,  although 
the  acid  is  not  used  up  in  the  reaction. 

The  velocity  of  inversion  by  acids,  or  by  water,  is  almost 
exactly  proportional,  in  dilute  solutions,  to  the  concentration 
of  the  hydrogen  ions,  and  is  expressed  by  the  equation 

~     =     K(Csugar  —  x)  X  (CH,o— x)  X  CH.  (i) 

In  dilute  solutions,  since  CH  and  (CHtO — x)  are  approximately 
constant  the  reaction  is,  apparently,  one  of  the  first  order. 
In  more  concentrated  solutions,  since  the  factor  (CfftO — x) 
changes  appreciably  in  value,  the  reaction  proves  to  be  one  of  the 
second  order.  Now  cane-sugar  has  the  same  "ether"  linkage, 
COC,  common  to  a  large  number  of  oxygen  compounds  which 
have  been  shown  to  have  basic  properties,  and  it  might  be  ex- 
pected to  form  tetravalent  oxygen  salts  of  the  same  general 
type,  R2O.HC1. 

Unfortunately,  cane-sugar  is  not  soluble  in  the  solvents 
from  which  we  could  expect  to  precipitate  its  hydrochloride. 
But  Hantzsch9  has  shown  that  cane-sugar,  just  as  dimethyl- 

i  J.  prakt.  Chem.  [2],  29,  385;  [2],  31,  307. 
»  Z.  physik.  Chem.,  28,  145. 
•Ibid.,  25,  144,  193. 
*  Pogg.  Ann.,  81,  413,  499. 
5  Z.  physik.  Chem.,  4,  226. 

8  Ber.  d.  chem.  Ges.,  13,  1696;  15,  2130,  2457,  2687;  16,  762;  17,  47,  495,  2165  5 
18,  3047;  20,  1836;  22,  318. 

7  J.  prakt.  Chem.  [2],  32,  32;  [2],  33,  265. 

8  Z.  physik.  Chem.,  10,  321. 

»  Ber.  d.  chem.  Ges.,  38,  2143. 


52 

pyrone,  glucose  and  other  weak  bases,  lowers  to  a  small  ex- 
tent the  conductivity  of  sulphuric  and  hydrochloric  acid  solu- 
tions. Dulcite1  forms  a  hydrochloride,  a  hydrobromide,  and 
a  hydriodide  which  can  be  isolated. 

Furthermore,  sugars  show  their  basic  properties2  in  forming 
complex  salts,  as  Rosenheim3  has  pointed  out.  We  are, 
therefore,  justified  in  concluding  that  sugars  do  form  a  very 
small  amount  of  salt  in  acid  solutions.  Of  course  the  cane- 
sugar  is  such  a  weak  base  that  these  salts  would  be  nearly 
completely  hydrolyzed. 

The  relation  between  the  concentrations  of  the  sugar,  acid 
and  salt  formed  are  expressed  as  follows: 

(C.HU0B)20  +  H  +  Cl    ^t     (C6Hn05)2OH  +  Cl 


or 

(G  — *)  XCff  =  KhydCs  =  *j^Cs 

Kb 

and  (Cb  —  x)  XCffX  CCi  =  ^~Cm,  (2) 

J^b 

in  which  Cb  represents  the  initial  concentration  of  the  sugar, 
Cs  the  concentration  of  the  complex  sugar  cathion  at  the  mo- 
ment considered,  and  Cm  that  of  the  undissociated  complex 
sugar  salt.  The  amount  of  sugar  changed  into  salt  is  so  small 
that  (Cb — x),  CH  and  Cahave  practically  the  value  which  they 
would  have  if  no  salt  were  formed. 

If,  now,  the  complex  sugar  cathion  is  hydrolyzed  by  the 
water  according  to  the  following  equation,  in  which  Cs  and 
(CH*O— *)  represent 

(C6Hn05)2OH  +  H20     ^     2C6H1206  +  H, 
or 

1  Bouchardat:  Compt.  rend.,  74,  866.     Ann.  Chim.  Phys.  [41,  27,  145. 

2  Peligot:  Compt.  rend.,  7,  106,    Ann.  Chim.  Phys.  [2],  67,  113;  Violette:  Compt. 
rend.,  76,  485.     MaumenS:  Bull.  Soc.  Chim.  [2],  19,  289. 

•Ber.  d.  chem.  Ges.,  34,  3377;  35,  1115;  36,  1833;  37,  3662;  38,  2777. 


/ 

f    UNlVEf 


53 

*3 


X    (C//^  —  *),  (3) 


the  concentration  of  the  cathion  and  the  water  at  any  given 
moment,  it  follows  from  (2)  that  we  can  substitute  for  Cs 
the  value 


~  (Cb—x)  X  CH 


and  we  then  get 

dx  Kb 


X    Cff  X 


which  is  actually  what  is  found  experimentally. 

But  if  the  undissociated  salt  were  the  substance  undergoing 
hydrolysis, 

(C,HU06),O.HC1  +  H20    »+     2C6H1206  +  H  +  Cl 
or 

X    (C^2o  —  *),  (5) 


it  follows  from  (2)  that  we  can  substitute  for  Cm  the  value 

(Cb  —  x)  XCffX  Ca, 


•ft-  a/  Baffin 

and  we  then  get 


A 


X  C^  X  Ca  X  (Czr.0-*),  (6) 


in  which  (C3  —  x)  is  the  concentration  of  the  sugar  at  any 
moment  and  (CHyO  —  x)  is  that  of  the  water.  In  dilute  solu- 
tions, (CH^0  —  x)  hardly  changes  in  value,  and  the  reaction  ap- 
pears to  be  monomolecular. 

But  equation  (6)  does  not  express  the  quantitative  relations 
actually  found  to  hold  experimentally.  It,  therefore,  follows 
that  the  undissociated  salt,  Cm,  cannot  be*  the  substance  which 
is  chiefly  undergoing  hydrolysis,  although  it  may  do  so  to  a 
small  extent. 


54 

We  are  then  led  back  to  the  idea  that  (i)  the  amount  of  com- 
plex cathion  is  directly  proportional  to  the  product, of  the  con- 
centrations of  the  sugar  and  of  hydrogen  ions,  whether  the 
hydrogen  ions  came  from  strong  acids,  weak  acids  or  water; 
(2)  the  velocity  of  inversion  of  cane-sugar  is  also  proportional 
to  the  product  of  the  concentrations  of  the  sugar  and  of  the 
hydrogen  ions.  It  is,  therefore,  possible,  and  from  the  above 
evidence  probable,  that  cane-sugar  is  inverted  or  hydrolyzed 
in  aqueous  solutions  containing  hydrogen  ions  because  the 
hydrogen  ions  first  unite  with  the  sugar  and  form  a  com- 
plex cathion  which  is  then  decomposed  by  the  water  into  glu- 
cose, fructose  and  hydrogen  ions. 

Exactly  analogous  to  the  inversion  of  cane-sugar  and  other 
sugars  is  the  hydrolysis  of  the  diethylacetal  of  glyceric  alde- 
hyde,1 

CH2OHCHOHCH(OC2H5)2, 
a-methylglucoside,2 

H 
CH2OHCHOHCH(CHOH)2COCH3, 


-O 


and  other  similar  compounds  by  dilute  aqueous  solutions  of 
acids.  These  substances  are  not  hydrolyzed  in  alkaline  solu- 
tions. In  all  of  these  cases  the  "ether  linkage"  seems  to  be 
the  point  of  attack.  This  would  be  expected  if  intermediate 
salt  formation  takes  place  and  is  followed  by  hydrolysis,  as 
discussed  above: 

H  +       - 

CH2OHCHOHCH(CHOH)2COCH3  +  H  +  Cl  +  H2O      t, 


'  --  O 

H     + 
CH2OHCHOHCH(CHOH)2C—  OCH8  +  Cl  +  H2O 


»  Wohl:  Ber.  d.  chem.  Ges.,  31,  1796. 
*  Fischer:  Ibid.,  26,  2400;  27,  2478. 


55 

H  + 

CH2OHCHOHCH(CHOH)2— C— OH  -|-  H  +  Cl  +  CH3OH. 

O 


ON  THE  REACTIONS  OF  CARBONYL  COMPOUNDS  WITH  HYDROXYI/- 
AMINE  AND  WITH  HYDROXYI^AMINE  HYDROCHI,ORIDE. 

Theoretical. 

Ketones  and  aldehydes  react  with  hydroxylamine  and  form 
oximes.  Nothing  has  been  known  up  to  this  time  of  the  ra- 
pidity or  order  of  the  reaction  of  various  carbonyl  compounds 
with  the  hydroxylamine.  In  Victor  Meyer's1  directions  for 
making  acetoxime  from  acetone  and  hydroxylamine,  the 
mixture  stood  over  night.  I  have  found,  however,  that  the 
reaction  is  practically  finished  in  a  few  minutes  at  100°  and  in 
2  hours  at  65  °.  The  reaction  is  approximately  one  of  the  sec- 
ond order.  Although  the  reaction  certainly  goes  nearly  to 
completion,  it  seems  to  be  reversible. 

(CH3)2CO  +  NH2OH     ^    (CH3)2C  :  NOH  +  H2O       (i) 

Since  diethyl  ketone  reacts  more  slowly,  and  acetaldehyde 
more  rapidly,  with  hydroxylamine  than  does  acetone,  it  is 
probable  that  the  so-called  space  interference  influences  these 
reactions.  The  velocity  constant  for  the  reaction  between 
acetaldehyde  and  hydroxylamine  in  o.i  N  solutions  at  io°.5 
is  0.035.  The  constant  for  o.i  N  acetone  and  o.i  N  hydroxyl- 
amine at  i°  is  0.0040,  while  at  65°  it  is  o°.o6o.  The  constant 
for  o.i  N  diethylketone  and  o.i  N  hydroxylamine  at  35°  is 
0.005,  while  at  65°  it  is  o.oio.  These  constants  are  calculated 
on  the  assumption  that  the  reaction  goes  to  completion.  This 
is  probably  not  true,  as  the  reaction  seems  to  be  reversible ; 
but  the  reaction  goes  so  nearly  to  completion  that  only  a  small 
error  is  involved  in  the  assumption  made  above. 

When  hydrochloric  or  hydrobromic  acid  is  added  to  a  mix- 
ture of  acetone  and  hydroxylamine,  the  reaction  progresses  far 
more  rapidly,  just  as  is  the  case  in  ester  catalysis,  cane-sugar, 

1  Ber.  d.  chexn.  Ges.,  15,  1324. 


56 

inversion,  etc.  This  at  once  makes  us  suspect  that  the  hydro- 
chloric acid  acts  as  a  catalytic  agent  because  it  acts  upon  the 
base  hydroxylamine  and  produces  a  greater  concentration 
of  the  hydroxylammonium  ions,  which  then  react  more  rapidly 
with  the  acetone. 

(CH3)2CO  +  NH2OH  +  H  -f  Cl 

(CH3)2CO  +  NH3OH  +  Cl 

(CH3)2C(OH)NH2OH  +  Cl 

(CH3)2C  :  NOH  +  Cl  +  H2O 
H 

(CH3)2C  :  NOH  +  H  +  Cl  +  H2O  (2) 
Strangely  enough,  however,  when  hydrochloric  acid  is  ad- 
ded to  accelerate  the  reaction  the  process  does  not  go  to  com- 
pletion as  it  practically  does  when  no  acid  is  present.  The 
reason  for  this  is  now  clear.  In  the  presence  of  hydrochloric 
acid  acetoxime  is  partly  hydrolyzed  into  acetone  and  hydroxyl- 
amine hydrochloride.  Janny's1  statement  that  acetoxime  is 
completely  hydrolyzed  by  hydrochloric  acid,  and  similar 
statements  in  text-books,  are  erroneous.  I  have  found  that 
a  large  excess  of  acid  is  not  sufficient  to  hydrolyze  the  acetox- 
ime completely.  In  fact  there  is  always  an  equilibrium  es- 
tablished and  the  equilibrium  point  is  the  same  whether  acet- 
oxime is  treated  with  a  given  amount  of  hydrochloric  acid 
at  a  given  temperature,  or  the  equivalent  quantities  of  ace- 
tone, hydroxylamine  and  hydrochloric  acid  are  brought  to- 
gether under  the  same  conditions. 

Especially  important,  however,  is  the  fact  that  a  change 
in  the  amount  of  hydrochloric  acid  effects  a  change  in  the  equi- 
librium in  the  system  expressed  in  the  following  equation : 

(CH8)2C  :  NOH  +  H  +  Cl  +  H2O    ^ 

(CHS)2C  :  NHOH  +  H2O  +  Cl    ^ 

(CH3)2Colf  NH2OH  +  Cl    ^ 

(CHs)aCO  -j-  NH3OH  +  Cl     (3) 

1  Ber.  d.  chem.  Ges..  16,  170. 


57 

The  water  is  probably  added  to  the  double  bond  in  all  such  re- 
actions before  the  products  of  hydrolysis  are  formed.  It 
has  been  found  that  an  increase  in  the  amount  of  hydro- 
chloric acid  causes  a  very  decided  increase  in  the  amount  of 
hydroxylamine  hydrochloride,  although  the  addition  of  sev- 
eral molecules  of  hydrochloric  acid  does  not  cause  complete 
hydrolysis  of  the  acetoxime.  This  is  a  very  important  case 
and  probably,  with  the  one  of  Bauer  and  Voermann,1  is  the 
confirmation  of  the  ideas  advanced  by  Acree  and  Johnson,2 
that  in  some  reversible  reactions  it  will  be  found  that  a  change  in 
the  concentration  of  the  catalyzer  will  produce  a  change  in 
the  equilibrium  of  the  system.  That  there  is  a  real  change 
in  the  equilibrium  was  shown  quite  definitely  by  the  fact  that 
the  same  equilibrium  point  is  established  whether  the  acid 
be  added  to  acetoxime  in  solution  or  to  the  equivalent  concen- 
trations of  acetone  and  hydroxylamine.  The  cause  of  this 
change  in  equilibrium  is  probably  the  following.  The  acet- 
oxime is  a  very  weak  base,  as  has  been  established  by  Walker.3 
There  is,  however,  an  error  in  Walker's  work,  due  to  the  fact 
that  he  did  not t  take  into  consideration  the  hydrolysis  of  the 
acetoxime  and  the  formation  of  hydroxylamine  hydrochloride 
which  is  far  less  hydrolyzed  than  the  acetoxime.  The  acetox- 
ime is  a  very  weak  base  and  its  hydrochloride  is  greatly  hy- 
drolyzed in  water  solution.  I  have  been  able  to  show  this 
by  the  simple  process  of  titrating  0.1243  gram  acetoxime  in 
10  cc.  water  containing  methyl  orange  with  o.  i  N  hydrochloric 
acid;  it  requires  only  0.25  cc.  of  the  total  molecular  quantity, 
17.00  cc.,  to  give  the  solution  a  pink  color.  In  the  solution 
of  the  acetoxime  and  hydrochloric  acid  there  can  be  only 
a  small  amount  of  the  acetoxime  cathion,  which  could  be 
calculated  if  the  affinity  constant  of  the  base  were  known. 
If  the  data  in  the  experimental  portion  were  a  little  more 
accurate  they  could  be  used  to  determine  the  affinity  constant 
of  the  acetoxime.  The  small  amount  of  acetoxime  cathion 
is  almost  surely  the  substance  in  equilibrium  with  the  hydroxyl- 
ammonium  ion  and  acetone  as  follows: 

1  Z.  physik.  Chem.,  52,  467. 
»Am.  Chem.  J.t  37,  410. 
*  Z.  physik.  Chem.,  4,  330. 


58 
(CH3)2C :  NHOH  +  H2O    ^     (CH3)2CO  +  NH3OH. 

But  the  hydroxylamine  is  such  a  strong  base  that  its  hydro- 
chloride  is  practically  not  hydrolyzed  at  all  and  reacts  only 
faintly  acid  to  methyl  orange.  The  addition  of  more  hydro- 
chloric acid  then  causes  the  formation  of  more  acetoxime 
cathion  from  the  acetoxime  then  present,  but  does  not  change 
appreciably  the  concentration  of  the  hydroxylammonium 
ions  then  present.  Since  this  acetoxime  cathion  formed  must 
change  to  conform  to  the  equilibrium  expressed  above,  more 
acetone  and  more  hydroxylammonium  ions  must  be  formed 
from  the  acetoxime  cathion  and  water  to  restore  the  equi- 
librium. Since  the  hydroxylammonium  ion  is  not  appreciably 
changed  into  hydrogen  ions  and  hydroxylamine,  the  change 
in  equilibrium  is  accompanied  by  disappearance  of  the  hydro- 
gen ions.  Of  course  the  real  equilibrium  between  the  acetoxime 
cathion  and  the  acetone  and  hydroxylammonium  ion  is  not 
changed,  but  the  apparent  equilibrium  between  the  acetone, 
total  hydroxylamine,  salt,  and  total  acetoxime  and  salt  is 
changed. 

The  fact  that  the  equilibrium  is  changed  in  Tables  XXIX. 
to  XLJI.  by  change  in  concentration  of  the  acid  is  of  very  great 
importance  in  the  theory  of  the  catalytic  influence  of  acids 
on  reversible  reactions.  Practically  the  only  well-known 
reversible  reaction  influenced  catalytically  by  hydrogen  ions 
is  the  reversible  reaction  between  organic  acids  and  alcohols 
on  the  one  hand  and  esters  and  water  on  the  other.  In 
this  reaction  the  equilibrium  is  not  disturbed  appreciably  by 
change  in  the  concentration  of  the  hydrogen  ions.  The  reason 
for  this  is  that  little  of  the  hydrogen  ions  unites  with  either  or- 
ganic acid  or  ester,  whereas  in  the  work  quoted  above  on  the 
saponification  of  the  oxime,  nearly  all  of  the  hydroxylamine 
exists  in  the  form  of  cathions.  This  subject  will  be  treated 
in  detail  in  the  section  dealing  with  esterification  and 
saponification. 

Furthermore,  the  very  interesting  fact  was  established  that 
the  equilibrium  in  a  given  system  changes  with  temperature. 
A  rise  in  temperature  from  io°,5  to  92°  produces  a  gradual 


59 

increase  in  the  amount  of  hydroxylamine  hydrochloride  and 
acetone  necessary  for  equilibrium  with  the  acetoxime  hydro- 
chloride,  the  equilibrium  at  the  higher  temperatures  being 
established  very  quickly.  A  decrease  in  temperature  brings 
about  the  reverse  process,  and  the  same  equilibrium  is  found 
at  a  given  temperature  as  was  established  when  the  temper- 
ature was  rising.  It  is  very  probable  that  the  decided  appar- 
ent increase  with  rise  in  temperature  in  the  affinity  constant 
of  acetoxime  recorded  by  Walker  is  due  to  the  above  causes. 
With  rise  in  temperature  there  is  an  increase  in  the  amount  of 
the  hydroxylamine  and  its  hydrochloride.  Since  hydroxyl- 
amine is  a  much  stronger  base  than  acetoxime,  a  greater  per- 
centage of  the  hydrogen  ions  disappear  in  the  formation  of 
hydroxylammonium  ions  at  the  higher  temperature,  and  hence 
the  acetoxime  seemed  to  Walker  to  be  a  stronger  base  than 
it  really  is.  The  point  is  that  at  the  higher  temperature 
the  hydrogen  ions  do  not  disappear  in  the  formation  of  acetox- 
ime cathion,  but  in  the  formation  of  hydroxylammonium  ions. 
The  change  in  equilibrium  with  change  in  temperature  may 
be  the  result  of  exothermic  or  endothermic  reactions,  or  change 
in  the  affinity  constant  of  the  bases  with  change  in  tempera- 
ture, or  may  come  from  other  causes,  which  can  only  be  de- 
termined by  further  work. 

That  there  is  really  equilibrium  between  the  acetone  and 
hydroxylammonium  ions  on  the  one  hand  and  the  acetoxime 
cathions  on  the  other  in  a  solution  of  these  substances  is  shown 
further  by  the  fact  that  the  addition  of  acetone  to  the  solu- 
tion causes  a  decrease  in  the  amount  of  hydroxylamine  hy- 
drochloride, whereas  the  addition  of  hydrochloric  acid  causes 
an  increase  in  the  concentration  of  the  hydroxylamine  hy- 
drochloride and  its  ions.  If  equation  (3)  really  represents 
the  reaction  we  can  express  the  equilibrium  condition  by  equa- 
tion (4), 

C acetone    X    Chydam  -rr  r\ 

7^ —  <K>  (4; 


in   which   Cacetone,  Chydam  and  Cacoxcat  represent  the  concen- 
trations of  the  acetone,  hydroxylammonium  ions  and  acetox- 


6o 

ime  cathions,  respectively.  Now  the  concentrations  of  the 
acetone,  hydroxylamine  ions  and  total  acetoxime  and  its  salt 
can  be  determined  analytically  at  any  moment  by  the  above 
method.  But  the  value  of  Cacoxcat  can  not  be  determined 
accurately  by  the  analytical  method  employed  in  the  present 
communication.  A  very  close  approximation  can  be  made 
to  it,  however,  when  the  concentrations  of  the  acetone,  hy- 
droxylamine and  hydrochloric  acid  have  somewhere  near  the 
same  values. 

Since  the  acetoxime  is  a  very  weak   base,  the  value  of 
*ne  equilibrium  equation, 

(CH8)2C  =  NHOH     *^t     (CH3)C  =  NOH  +  H 


Cacox  X  Cff 

is  a  very  small  part,  probably  only  about  5  per  cent  of  the 
value  of  Cacox,  the  concentration  of  the  free  base  acetoxime. 
Instead  of  Cacoxcat  in  equation  (4)  we  can  substitute 

K    Cacox    X    Cff, 

and  we  then  get  equation  (6). 

C- acetone    X    ^hydam  rs-Ts-t  rsir  /^-\ 

Cacox  X  Cff  ' 

That  this  equation  holds  very  well  experimentally  is  made 
evident  by  a  glance  at  Tables  XXV.  to  XLV.  The  value  of 
K"  is  about  1.25  when  the  concentrations  of  the  substances 
do  not  vary  widely.  But  when  an  excess  of  acid  is  added,  the 
value  of  the  constant  decreases  considerably  as  was  predicted. 
The  reason  for  this  is  that  with  the  addition  of  the  acid  the 
percentage  of  increase  in  CH  is  much  greater  than  the  percentage 
of  decrease  in  Cacox,  and  consequent  increase  in  Cacetone  and 
C/tydam'  anc*  hence  the  value  of  K"  decreases.  •  But  if  we 
knew  the  value  of  Cacoxcat  and  could  substitute  the  data  in 
equation  (4)  there  is  hardly  any  doubt  that,  with  a  good  an- 
alytical method,  good  constants  could  be  obtained.  The 
fact  that  equation  (6)  gives  a  fair  constant,  which  decreases 


6i 

with  large  increase  in  Cff,  shows  that  equation  (2)  represents 
the  real  equilibrium  conditions. 

That  equation   (2)   represents  the  real  equilibrium  condi- 
tion which  may  be  written  simply  in  the  following  equation, 

(CH3)2CO  +  NHSOH    T±     (CH3)2C  =  NOH  +  H,   (7) 


because  the  concentration  of  the  water  hardly  undergoes 
change,  is  further  shown  by  the  data  in  Tables  XI.  to  XVI. 
inclusive. 

When  acetone  and  hydroxylamine  hydrochloride  are  brought 
together  in  equivalent  quantities,  equation  (7)  should  repre- 
sent the  reaction,  and  the  following  differential  equation  should 
represent  the  course  of  the  reaction. 

A  is  the  original  concentration  of  the  acetone  and  hydroxyl- 
amine in  gram  molecules  per  liter,  x  is  the  change  in  con- 
centration of  each  in  the  time  t,  K  is  the  velocity  constant 
for  the  reaction  on  the  left  in  equation  (7)  and  Kt  the  velocity 
constant  for  the  reaction  on  the  right.  When  acetoxime  and 
acids  are  brought  together  and  react  according  to  equation 

(7)  the  same  differential  equation  (8)  can  be  used.     Equation 

(8)  can  be  written  in  the  form: 

doc 


fKA2      2KAX 
1  Ki  Ki 


or 


62 

Reference  to  Tables  XI.  to  XVI.  shows  that  equation  (9)  gives 
as  nearly  a  constant  value  for  Kj  as  the  errors  of  the  method 
will  permit.  A  further  discussion  of  this  reaction  will  be  given 
in  a  subsequent  paper. 

The  action  of  carbonyl  compounds  on  the  free  bases  and 
salts  of  oximes,  hydrazines,  semicarbazides  and  amines  is  be- 
ing continued  in  this  laboratory. 

EXPERIMENT  AI,. 

Preparation  of  Acetoxime. 

Twenty-five  grams  of  hydroxylamine  hydrochloride  were 
dissolved  in  30  cc.  water  at  5°  and  added  to  a  solution  of  15 
grams  of  sodium  hydroxide  in  20  cc.  water  at  5°;  25  grams  of 
acetone  were  then  added.  The  temperature  immediately 
rose  to  45°.  The  mixture  was  then  warmed  for  30  minutes 
at  60°,  and  then  cooled  in  ice.  When  the  precipitate  of  acet- 
oxime  was  filtered  off  and  dried,  it  weighed  22  grams.  When 
it  was  recrystallized  twice  from  water  it  melted  at  60°  to  62°. 
0.1243  gram  in  10  cc.  water  required  0.25  cc.  o.i  N  hydrochloric 
acid  to  give  a  pink  color  with  methyl  orange. 

Analytical  Method. 

In  the  two  following  tables  there  is  given  a  general  resume* 
of  the  experiments  instituted  to  learn  the  best  analytical 
method  for  the  following  reactions.  It  was  apparent  from 
the  work  of  Adams1  and  Haga,2  that  the  iodometric  method 
is  far  better  than  the  one  involving  the  use  of  Fehling's  solu- 
tion. Since  the  work  of  Adams  leaves  no  doubt  that  the  use 
of  sodium  phosphate  in  the  iodometric  method  is  better  than 
the  use  of  sodium  bicarbonate  we  carried  out  a  number  of  ex- 
periments to  ascertain  the  best  concentrations  of  sodium  phos- 
phate, iodine,  etc.,  for  our  purpose.  The  tables  show  how  the 
amount  of  iodine  required  varies  with  the  other  conditions 
when  the  iodine  is  added  to  the  hydroxylamine  solution.  Since 
the  hydroxylamine  reacts  nearly  quantitatively  with  the  io- 
dine according  to  the  equation 

»  Am.  Chem.  J.,  28,  200. 
»  J.  Chem.  Soc.,  51,  794. 


63 
2NH2OH  +  2l2    •**•     N20  +  H20  +  4HI, 

one-half  the  molecular  weight  of  hydroxylamine  hydrochlor- 
ide  is  the  number  of  grams  used  in  a  liter  to  make  the  normal 
solutions. 

The  method  finally  adopted  was  the  addition  of  about  10  cc. 
of  the  hydroxylamine  solution  to  an  excess  of  iodine  in  10  cc. 
of  10  per  cent  sodium  phosphate  solution,  and  titration  of  the 
excess  of  iodine  with  o.  i  N  sodium  thiosulphate  solution.  The 
results  are  given  in  Table  III.  All  the  necessary  check  experi- 
ments were  made  to  show  that  small  quantities  of  sodium 
phosphate,  sodium  dihydrogen  phosphate,  acetoxime  and 
acetone  were  without  much  influence  on  the  titrations.  The 
method  is  poor  but  is  sufficiently  accurate  to  make  the  pre- 
liminary study  of  the  problem. 

Table  I. 

Cc.  0.0851  N  Cc.  0.0858  N  idoine  required. 

NH2OH.HC1  Na2HPO4. 

solution. 

IO 
IO 
IO 

7 
Calculated  10  cc.  =  9.96  cc.  iodine. 

Table  II. 

Cc.  0.0853  N  iodine  required. 
Na3HP04. 


0.3  gram. 

0.5  gram. 

Kxcess. 

8.69 

10-54 

IO.I2 

8    72 

II    O7 

9.6O 

IO.Q4. 

7.7.5 

Cc.  0.1008  N 

IO  CC. 

NH2OH. 

i  gram  +8  cc. 

10  per  cent 

HC1. 

0.5  gram. 

0.7  gram. 

i  gram. 

2  grams,     o.i  N  KOH. 

solution. 

IO 

12 

-65 

12 

.65 

13 

.41 

13 

.66       13. 

00 

12 

.87 

IO 

12 

.02 

12 

.67 

13 

•39 

13 

•83          12. 

96 

13 

.13 

IO 

12 

.19 

12 

.65 

13 

•15 

13 

.82          12. 

95 

13 

.IO 

IO 

12 

.21 

12 

•74 

13 

.20 

13 

.06 

10 

12 

.85 

13 

.20 

13 

.07 

10 

13 

.15 

13 

.28 

» 

12 

•  97 

IO 

12 

.96 

13 

.20 

12 

.82 

12 

.85 

Calculated 

IO  CC. 

-  — 

II.7< 

")  CC. 

iodine. 

64 
Table  III. 

Cc.  0.1008  N  Cc.  0.0853  N 

NH2OH.HC1.  iodine  required. 

10  13.38 

10  13.19 

10  13.31 

10  13.19 

Calculated  10  cc.  =  11.79  cc.  iodine. 


In  all  of  the  following  work  on  the  reactions  between  car- 
bonyl  compounds  and  hydroxylamine,  the  amount  of  hydroxyl- 
amine,  or  its  hydrochloride,  left  unchanged  in  10  cc.  of  the 
solution,  corresponds  to  the  number  of  cc.  iodine  required. 
Since  the  tables  give  also  the  amount  of  iodine  required  for  the 
total  hydroxylamine  added,  or  for  that  formed  by  the  com- 
plete hydrolysis  of  the  acetoxime  added,  it  is  evident  that 
these  data  enable  us  to  calculate  the  concentrations  of  the  ace- 
tone, hydroxylamine  and  acetoxime.  In  practically  all  cases 
the  concentrations  used  are  such  that  about  12.50  cc.  o.i  N 
iodine  would  be  required  to  react  with  the  total  amount  of 
hydroxylamine,  free  and  combined.  In  order  to  save  space, 
therefore,  I  have  desisted  from  giving  this  enormous  amount 
of  data  in  the  tables,  and  have  furnished  only  the  figures 
necessary  to  calculate  the  results. 

Velocities  of  the  Reactions  between  Hydroxylamine  and  Carbonyl 

Compounds. 

The  solution  of  hydroxylamine  used  in  the  following  tables 
was  made  by  treating  3.4725  grams  NH2OH.HC1  with  50  cc. 
N  NaOH  and  diluting  to  500  cc.  The  acetone  solution  was 
made  by  diluting  1.466  grams  acetone  to  250  cc.  with  water. 
A  is  the  number  of  cc.  iodine  solution  used  up  by  10  cc.  of  the 
reaction  mixture.  Five  cc.  hydroxylamine  solution  used  up 
12.76  cc.  iodine  (A). 


Table  IV. 

49.4  cc.  o.ioi  acetone  solution  and  50  cc.  o.i  N  NH2OH  solu- 
tion at  i°.    A  =   12.67  cc. 

t.                                   0.0853  N  iodine.  AK. 

0.5                                          12.67  

2.1                                          12.67  

4-5                             12.67  

IlS.O                                         10.05  0.0022 

227.7                                           6.71  O.OO39 

304.5                                           5-50  0.0043 


Table  V. 

49.4  cc.  o.ioi  N  acetone  solution  and  50  cc.  NH2OH  solution 
at   65°.     A  =  12.76. 

t.                       ,..,.        0.0853  N  iodine.  AK. 

I.O                                          12. 6O  (O.OI27) 

4.1                                          10.26  0.0585 

8.0                               8.42  0.0644 

13.1                        8.70  0.0354 

30.1                           6.14  0.035 

65.0                           2.87  0.053 

105.5                               J-72  0.060 

148.2                               1.15  0.068 


Table  VI. 

50.3  cc.  0.0994  N  (CjHgJgCO  solution  and  50  cc.  o.i  N  NH2OH 
solution  at  35°.     A  =  n.Socc. 

t.                                       0.0882  N  iodine.  AK. 

5                                 H.49  0.0054 

20                   11.07  0.0033 

41                     9.71  0.0052 

66              8.92  0.0049 

86              8.24  0.0050 

122              7.10  0.0054 

173              6.23  0.0057 


66 

Table  VIL 

50.3  cc.  0.0994    N    (C2H5)2CO  solution  and    50  cc.  o.i  N 

NH2OH  solution  at  65°.     A  =  12.45  cc.     Correction:    5   cc. 
solution  used  0.56  cc.  0.0882  N  iodine  solution. 

t.                                     0.0882  N  iodine.  AK. 

i                             12.31  o.on 

5.5                          11.72  o.on 

2O. I                                       IO.IO  O.OII 

39.1                                          8.38  0.012 

63.1                                          8.24  O.O08 

91.9                            7.88  o.oio 

142.5                            4.77  o.oii 

221.0                                          3-73  0.0105 

2880.0                                          1.37  


Table  VIII. 

1.142  grams  CH3COH  diluted  to  250  cc.  Of  this  solution 
48.15  cc.  is  equivalent  to  50  cc.  NH2OH  solution.  5  cc. 
CH3COH  solution  used  up  0.50  cc.  iodine  at  35°. 

48.15  cc.  0.104  N  CH3COH  solution  and  50  cc.  o.i  N 
NH2OH  at  10.5°.  A  =  12.06  cc. 

t.  0.0882  N  iodine.  AK. 

5.9  IO.72  O.O29 

15.7  8.01  0.036 

34-5  5.67  0.035 

55-2  4-19  0.036 

81.3  2.34  0.053 


Table  IX. 

48.15    cc.  0.104  N    CH3COH    solution  and    50  cc.    o.i  N 
NH2OH  solution  at  35°.     A  =  11.90  cc. 

/.  0.0882  N  iodine. 

I  9.58 

3-66  4.46 

6.3  1.27 

11.5  J-87 

35-8  1.30 


67 

On   the  Hydrolysis  of  Acetoxime  by  Water  and  Acids,  and  the 

Equilibrium  between  Acetoxime  Hydrochloride  and 

Acetone  and  Hydroxylamine  Hydrochloride. 

In  order  to  learn  the  rapidity  of  hydrolysis  of  acetoxime  by 
water  and  acids  and  the  equilibrium  point  between  the  acet- 
oxime or  its  hydrochloride,  and  the  acetone  and  hydrox- 
ylamine  or  its  hydrochloride  the  following  experiments  were 
instituted.  The  results  show  that  the  equilibrium  point  changes 
with  temperature.  The  bearing  of  this  has  been  discussed  in 
the  theoretical  portion. 

In  making  the  solutions  3.6789  grams  of  acetoxime  were 
diluted  to  500  cc.  with  water;  50  cc.  of  this  solution  were  mixed 
with  50.38  cc.  o.i  N  hydrochloric  acid  solution  for  hydroly- 
sis. Ten  cc.  of  the  mixture  were  withdrawn  at  each  time 
period  and  run  into  an  excess  of  0.0853  N  iodine  and  10  cc.  of 
10  per  cent  disodium  hydrogen  phosphate  solution  kept  at  o°. 
The  excess  of  iodine  was  titrated  with  sodium  thiosulphate 
solution.  Column  II.  gives  the  amount  of  iodine  used  up  by 
the  hydroxylamine,  or  its  hydrochloride,  formed. 


Table  X. 

Hydrolysis  of  acetoxime  with  water  alone.  0.3650  gram 
acetoxime  was  diluted  to  100  cc.  with  water  and  the  tempera- 
ture kept  at  65°. 

t.  Cc.  iodine  0.0882  N. 

0  1.18 
126                                                0.73 

1  day  0.91 
4  days                                     0.71 


To  10  cc.  was  added  i  cc.  o.i  N  hydrochloric  acid  solution, 
and  the  mixture  was  heated  30  minutes  at  65  °.  The  solution 
then  required  3.44  cc.  of  iodine  solution. 


68 


Table  XL 

,50  cc.  acetoxime  solution  and  50.38  cc.  o.i  N  HBr  at  2C 

t.  0.0853  N  iodine. 

1  O.4I 

2  0.66 

3  0.76 


5 
9 

12 

18 

22 

35 


0.90 

1.20 
1.20 
I.4I 

1-59 
2.08 


Table  XII. 

50  cc.  acetoxime  solution  and  50.38  cc.  o.i  N  HBr   at  3°. 
j^ 
TZ^=  0.197.     A  =  13  cc.  0.0853  N  iodine  solution. 


5 

15 
34 
48 
61 

93 
120 

338 
426 


0.0853  N  iodine. 

0.88 
1.76 
2.23 

2.51 
2.88 

3-67 
3-66 
4.00 


0.0029 
0.0018 

O.OOII 

0.00096 
0.00095 

O.OOII 


Table  XIII. 

50  cc.  acetoxime  solution  and  50.38  cc.  o.i   N  HBr  at  nc 
-=  0.269.     A  =  13  cc.  0.0853  N  iodine  solution. 


t. 

2 

4 

7-i 
10 

15 

21 

25.5 

38 

60 


0.0853  N  iodine. 
0.96 
1.22 

1-55 
2.70 
2.76 
3-94 
4-30 
4.16 

4-44 


O.OO5O 
O.0032 
O.O024 
0.0035 
0.0025 
0.0036 
O.O046 
O.OO24 


69 

Table  XIV. 

55.5  cc.  acetone  (1.466  gram  to  250  cc.)  and  50  cc.  NH2OH.HC1 

{3-4725   gram  to  500  cc.)   at   13.5°.  A  =  12.75  cc. 

t.  0.0853  N  iodine. 

0.88  9.27 

i .  67  8 . 20 

5-5  7.04 

9-0  5-54 

15-33  4-71 

20.5  4.83 

24-67  4-13 

48.12  5.01 

148.5  5.oi 


Table  XV. 
50  cc.  acetoxime  solution  and  50.38  cc.  o.i  N  HBr  at  27°. 

t.  0.0853  N  iodine. 

1.16  1.45 

2.O  2.15 

2.5  2.48 

6.0  4.19 

9.5  4-86 

14.0  5.06 

17.5  5.13 

21.5  5-12 

29.5  5-05 


Table  XVI. 

Suppression  by  KBr.  50  cc.  acetoxime  solution,  50.38  cc. 

o.i  N  HBr,  and  5.9555  grams  KBr  (10  mols.)  at  27°. 

t.  0.0853  N  iodine. 

1  1.47 

2  2.24 

4  3.45 

6  4.23 

7  4-44 
8.08  5.08 

10  5.27 

15  5.68 

3i  5.09 


70 

Table  XVII. 
50  cc.  acetoxime  solution  and  50.38  cc.  o.i  N  HBr  at  50°. 

t.  0.0853  N  iodine. 

1  4.44 

2  5.69 
10  5-97 
20  5.97 

45  5-95 

Table  XVIII. 
50  cc.  acetoxime  solution  and  50.38  cc.  o.i  N  HC1  at   27°. 

/.  0.0853  N  iodine. 

i.o  1.87 

1.5  2.10 

2-5  3-05 

4-0  3.65 

5-25  4-04 

7.16  4.79 

10. 16  5.39 

15-0  5-26 

31-0  5-87 

When  10  cc.  were  withdrawn  and  treated  to  boiling  for  a 
short  time  8.72  cc.  of  iodine  solution  were  required.  The 
remainder  of  the  above  mixture  was  heated  to  90°.  t  =  time 
after  reaching  90°. 

t.  0.0853  N  iodine. 

5  7.15 

20  7.08 

This  last  table  shows  the  change  of  equilibrium  with  change 
in  temperature. 

Table  XIX. 
50  cc.  acetoxime  solution  and  50.38  cc.  o.i  N  HC1  at  50°. 

t.  0.0853  N  iodine. 

5  5-6o 

10  6.08 

15  6.13 

20  6.01 

30  6.01 

45  6.15 

80  6.25 


Table  XX. 

Suppression  by  KC1,  50  cc.  acetoxime  solution,  50.38  cc. 
o.i  N  HC1,  and  3.73  grams  KC1  (10  mols.),  at  27°. 

t.  0.0853  N  iodine. 

1.16  i. 80 

2.42  2.79 

4.06  4.02 

5-67  4.15 

7-5  4.58 

9.06  5.29 

14-25  5.31 

23.8  5.20 

38.75  5-55 


Table  XXI. 

To  47.8  cc.  acetone  solution  (1.5166  grams  in  250  cc.)  was 
added  50  cc.  NH2OH.HC1  solution  (3.4725  grams  in  500  cc.) 
at  65°.  A  =  12.50  cc.  0.0882  N  iodine. 

t.  0.0882  N  iodine. 

5-33  6.76 

7.1  6.80 

37-33  6.56 

IO2-O  6.84 


Table  XXII. 

To  the  55.8  cc.  left  of  the  above  mixture  4.2  cc.  1.05  N  HBr 
at  65°. 

t.  0.0882  N  iodine. 

1.0  7.76 

4.1  8.06 

7-8  8.51 

43-6  8.15 


Equilibrium  was  thus  changed  by  a  change  in  concentration 
of  the  acid  present. 

In  the  3  following  tables  the  concentrations  are:  1.5166 
grams  of  acetone  diluted  to  250  cc. ;  3.4725  grams  hydroxylamine 
hydrochloride  to  500  cc. 


72 

Table  XXIII. 

47.8  cc.  acetone  solution  and  50  cc.  NH2OH.HC1  solution  at 
65°.     A  =  12.59  cc-  0.0882  N  iodine  solution. 

t.  0.0882  N  iodine. 

0.8  6.69 

1.5  6.76 

2.5  6.81 

6.0  6.83 

1440.0  6.94 

Table  XXIV. 

47.8  cc.  acetone  solution  and  50  cc.  NH2OHHC1  solution  at 
varying  temperatures.     At  65°.    A  =  12.59  cc- 

Temp.  Time.  0.0882  N  iodine. 

65°  2.8  6.50 

80°  20  7 . 50 

92°  46  7.81 

80°  80  7.59 

65°  102  6.63 

35°  285  5.80 

10.5°  181  4.81 


Change  in  Equilibrium  with  the  Change  in  Concentration  of  the 

Acetone. 

The  following  experiments  were  tried  in  order  to  study  the 
change  in  equilibrium  produced  by  change  in  the  concentra- 
tion of  the  acetone.  The  amount  of  hydroxylamine  hydro- 
chloride  was  constant.  The  value  of  K  gives  the  approximate 
constant  obtained  by  substituting  the  proper  data  in  the  form- 
ula 

(CH8)2CO  X  NH8OH    =     K 

fr^Tf  \  /"* "VT/^TT  \/  TT 

\\^ri^)^>==-  IN  \JjLjL.  /\  Jtl 

as  was  discussed  in  the  theoretical  portion.     In  the  small 
parentheses  in  the  headings  above  the  tables  the  molecular 


73 

quantities  of  acetone  are  placed  under  the  term  0.5  amount, 
etc.;  the  amount  of  hydroxylamine  hydrochloride  used  is  the 
unit  of  comparison. 

Table  XXV. 

24  cc.  o.ioi  N  acetone  solution  (0.5  amount  acetone),  26  cc 
water,  and  50  cc.  NH2OH.HC1  solution  (3.4725  grams  to  500  cc.) 
at   65°.     A  =  12.50  cc.  0.0882  N   iodine. 

t.  0.0882  N  iodine. 

3  8-80 

12.2  8.75 

21.75  8.80 

28  8.76 

Mean,     8 . 75 
K-x-s 

Table  XXVI. 

25  cc.  o.i  N  NH2OH.HC1  and  25  cc.  o.i  N  acetone  (i  amount 
acetone)  at  65°. 

t.  0.0882  N  iodine. 

5  6.76 

7  6.80 

IO2  6.84 


Mean,     6.80 
K  -  1.4 

Table  XXVII. 

15  cc.  0.5  N  acetone  (3  amounts  acetone),  10  cc.  water,  and 
25  cc.  o.i  N  NH2OH.HC1  at  65°.     A  =  12.50  cc. 

t.  0.0882  N  iodine. 

6.1  (3-15) 

13  3-57 

19-7  3-43 

45-8  3-48 

Mean,     3.50 
K=  1.2 


74 
Table  XXVIII. 

25  cc.  0.5  N  acetone  (5  amounts  acetone),  25  cc.  o.i   N 
NH2OH.HC1  at  65°.     A  =  12.50  cc. 

/.  0.0882  N  iodine. 

5.2  2.26 

24.3  2.26 

84.1  2.21 


Mean,     2 . 24 
K  -  i.i 


Change  in  Equilibrium  with  Change  in  the  Concentration  of  the 
Hydrochloric  Acid. 

As  was  discussed  in  the  theoretical  portion,  if  there  is  real 
equilibrium  between  the  acetoxime  hydrochloride,  and  the 
acetone  and  hydroxylamine  hydrochloride,  this  same  equi- 
librium point  should  be  attained  whether  acetoxime  be 
treated  with  hydrochloric  acid  or  acetone  be  heated  with  hy- 
droxylamine hydrochloride.  The  equilibrium  should,  further- 
more, be  changed  by  a  change  in  the  concentration  of  the  hy- 
drochloric acid.  In  general,  this  idea  is  perfectly  well  estab- 
lished by  the  following  experimental  data.  The  formula 


(CHS),CO  X  NH3OH 

~       — 
(CH3)2C  = 


seems  to  hold  very  well  for  those  solutions  containing 
amounts  of  acetone,  hydroxylamine,  hydrochloric  acid  and 
acetoxime  having  similar  concentrations. 


Acetone  +  NH2OH.HC1  Acetoxime  +  HC1 

HC1  varied.  HC1  varied. 


75 

Table  XXIX. 
(0.2  HC1) 

20  cc.  o.i  N  KOH,  5  cc.  0.5  N  acetone,  and  25  cc.  o.i  N 
NH2OH.HC1  at  65°. 

/.  0.0882  N  iodine. 

6  (2.80) 

23  2.44 

99  2 . 38 


Mean,     2.41 


Table  XXX. 
(0.2  HC1) 

25  cc.  o.i  N  acetoxime  (0.73  gram  to  100  cc.),  5  cc.  o.i  N 
HC1,  and  20  cc.  H2O  at  65°. 

t.  0.0882  N  iodine. 
6.5  2.96 

18.5  2.53 

73-5  2.82 

Mean,     2 . 89 


Table  XXXI. 
(0.6  HC1) 

5  cc.  0.5  N  acetone,  10  cc.  H2O,  10  cc.  o.i  N  KOH,  and  25  cc 
o.i  N  NH2OH.HC1  at  65°. 

t.  0.0882  N  iodine. 

7  4-97 

17  5-02 

40  5-05 

Mean,     5.01 
K  -  1.35 


76 

Table  XXXII. 
(0.6  HC1) 

25  cc.  o.i  N  acetoxime,  15  cc.  o.i  N  HC1,  and  10  cc.  H2O 
at    65°. 

/.  0.0882  N  iodine. 

10  5.07 

33  4-85 

145  5-00 

Mean,     4.97 


Table   XXXIII. 

(i  HC1) 
25  cc.  o.i  N  acetone  and  25  cc.  o.i  N  NH2OH.HC1  at  65° 

t.  0.0882  N  iodine. 

5  6.76 

7  6.80 

102  6 . 84 

Mean,     6.80 
K  =  1.4 


Table  XXXIV. 

(i  HC1) 

25  cc.  o.i  N  acetoxime  and  25  cc.  o.i  N  HC1  at  50°. 

/.  0.0882  N  iodine. 
15  6.13 

45  6.15 

80  6.25 


Mean,     6.17 


77 

Table  XXXV. 
(1.4  HC1) 

10  cc.  H2O,  5  cc.  0.5  N  acetone,  locc.  o.i  NHC1,  and  25  cc 
o.i  N  NH2OH.HC1  at  65°. 

t.  0.0882  N  iodine. 

8.5  7-29 

21  7.30 

66  7.37 

109  7.43 

Mean,     7.35 
K  -  i. 06 


Table  XXXVI. 
(0.8  HC1) 

20  cc.  o.iN   HC1,  5  cc.  H2O,  and  25  cc.  o.i  N  acetoxime 
at  65°. 

t.  0.0882  N  iodine. 

6  5.63 

27.33  5-74 

49  5.67 

Mean,     5.68 
K  -  i.i 


Table  XXXVII. 
(1.8  HC1) 

5  cc.  0.5  N  acetone,  20  cc.  o. i  N  HC1,  and  25  cc/o. i  N  NH,OH . 
HC1  at  65°. 

t.  0.0882  N  iodine. 

7  8.00 

27  7.96 

54  7-94 

Mean,     7.96 
K  -  0.94 


78 

Table  XXXVIII. 

(1.8  HC1) 

4.5  cc.  N  HC1,  20.5  cc.  H2O,  and  25  cc.  o.i   N  acetoxime 
at  65°. 

/.  0.0882  N  iodine. 

7  7.64 

23-5  7.76 

141  7.80 


Mean,     7.75 


Table  XXXIX. 

(3  HC1) 

5  cc.  0.5  N  acetone,  5  cc.  N  HC1,  15  cc.  H2O,  and  25  cc 
0.1    N    NH2OH.HC1  at  65°. 

t.  0.0882  N  iodine. 

II  8.30 

29  8.35 

41  8.44 

142  8.37 

Mean,     8 . 34 
K  =  0.58 


Table  XL. 
(2.5  HC1) 

6.25  cc.  i.o  N  HC1,  18.75  cc-  H2O,  and  25  cc.  o.i  N  acet- 
oxime  at   65°. 

/.  0.0882  N  iodine. 

12  (8.02) 

21  8.39 

47  8.34 

70  8.44 

Mean,     8.39 
K  =  0.68 


79 

Table  XLL 
d7  HC1) 

5.21  cc.  7.68  N  HC1,  5  cc.  0.5  N  acetone,  14.79  cc.  H2O,  and 
25  cc.  o.i  N  NH2OH.HC1  at  65°. 

/.  0.0882  N  iodine. 

15 

45 

Mean,     10 . 10 

Table  XLII. 

(5  HC1) 

12.5  cc.  N  HC1,  12.5  cc.  H2O,  and  25  cc.  o.i  N  acetoxime 
at  65°. 

/.  0.0882  N.  iodine. 

5-33  8.54 

20  8.52 

54  8.44 

Mean,     8 . 50 

The  three  following  tables  give  a  resume*  of  the  chief  results  ob- 
tained at  65°.  In  the  first  table  the  upper  column  gives  the 
number  of  cc.  used  for  the  titration.  The  solution  was  o.i  N 
with  respect  to  the  hydroxylamine  hydrochloride,  and  the 
concentration  of  the  acetone  was  0.5,  i,  3  or  5  times  o.i  N, 
as  indicated  in  the  second  column.  The  third  column  gives 
the  number  of  cc.  iodine  required  to  oxidize  the  hydroxylamine, 
or  its  salt. 

Table  XLIII. 

Cc.  solution  10  10  10  10 

Molecules  acetone         0.5  i  3  5 

Cc.  iodine  required        8.77  7. 44          3. 49  2. 24 

The  second  table  shows  the  change  in  equilibrium  with 
a  change  in  concentration  of  the  hydrochloric  acid. 


8o 

Table  XLIV. 

Cc.  solution: 
o.iNNH2OH.HCi 

•f  o.  i  N  acetone        10       10       10       10       10        10        10 
Molecules  HC1  0.2      0.6      i.o      1.4      1.8      3        17 

Cc.  iodine  required       2.41    5.01    6.80    7.35    7.96    8.34  10.10 

The  third  table  gives  the  equilibrium  attained  when  o.i  N 
acetoxime  is  treated  with  varying  amounts  of  hydrochloric 
acid.  For  a  given  amount  of  hydrochloric  acid  the  equilibrium 
point  is  practically  the  same  as  it  is  in  Table  XLIV. 

Table  XLV. 

Cc.  solution: 
o.  i  N  acetoxime 

4-  HC1  10        10        10        10        10        10        10 

Molecules  HC1          0.2      0.6      0.8      i.o      1.8      2.5      5 
Cc.  iodine  required  2.89    4.97    5.68    6.17    7.75    8.39    8.50 

ON  THE  REACTION  OP  ACETONE  WITH  PHENYLHYDRAZINE  AND 
PHENYLHYDRAZINE  HYDROCHLORIDE. 

A  preliminary  announcement  is  made  of  the  study  of  the 
action  of  acetone  on  phenylhydrazine,  and  on  its  hydrochloride. 
After  the  results  of  the  action  of  acetone  on  hydroxylamine 
had  been  obtained  it  was  seen  that  the  reaction  of  carbonyl 
compounds  with  hydrazines,  and  with  their  salts,  might  be 
reversible.  The  idea  seems  to  be  confirmed  by  the  experimen- 
tal data. 


(CH3)2CO  -f  H2N— NHC6H6 

(CH3)2C:NNHC6H5  +  H20; 

(CH3)2CO  -f  H3N— NHC6H5  +  Cl    *^S 

(CH3)2C  :  NNHC6H5H  -f  H2O  +  Cl. 

The  method  of  following  the  reaction  was  that  of  Meyer.1 
It  does  not  seem  to  work  well  in  the  case  under  consideration, 
but  further  study  may  lead  to  improvement.  The  two  following 

1  J.  prakt.  Chem.  [2],  36,  115. 


8i 

tables  show  that  while  the  reaction  between  phenylhydrazine 
and  acetone  seems  to  go  nearly  to  completion,1  the  phenyl- 
hydrazine hydrochloride  reacts  at  most  only  very  slowly  with 
the  acetone,  and  the  reaction  seems  to  be  reversible.  The  changes 
are  very  slow  in  comparison  with  those  between  acetone  and 
hydroxylamine  or  its  hydrochloride.  The  work  will  be  con- 
tinued and  the  results  reported  must  be  considered  only  tenta- 
tively. 

Table  I. 

50  cc.   phenylhydrazine  solution   (2.7028  grams  in   250.26 
cc.),  40  cc.  water,  and  10  cc.  0.5  N  acetone  at  27°. 

Cc.  iodine  solution 

Cc.  iodine  required  for  5  cc. 

required  for  phenylhydrazine 

/.  10  cc.  solution.  solution  at  22°. 

o  17.88  17.88 

5  13-62 

24  11.82 

40  10 . 30 

184  9.46 

1374  5-47 

4252  2.72 

5856  2.04 

8907  1.62  15.09 

Table  II. 

50    cc.    phenylhydrazine    hydrochloride    solution    (3.6113 
grams  in  250  cc),  40  cc.  water,  and  10  cc.  0.5  N  acetone  at  27°. 

Cc.  iodine  solution 
required  for  5  cc. 

Cc.  iodine  phenylhydrazine 

required  for  hydrochloride 

t.  10  cc.  solution.  solution  at  22°. 

o  17.23  17.23 

2  17.23 

2722  13.63  15.97 

4309  13.13 

738l  13.17  16.93 

ON  THE  FORMATION    AND   SAPONIFICATION   OF    ESTERS  AND   THE 
THEORY  OF  REVERSIBLE  CATALYTIC  REACTIONS. 

The  theory  of  the  reversible  reaction  between  organic  acids 

»  Strache:  Monats.  Chem.,  12,  524. 


82 

and  alcohols  on  the  one  hand  and  the  esters  and  water  on  the 
other,  has  been  discussed  in  some  detail  by  Zengelis,1 
Buler,2  Lapworth,3  Mellor,4  Kastle,5  Goldschmidt,6  Acree  and 
Johnson,7  and  especially  by  Stieglitz.8  While  the  theories 
held  by  individuals  vary  somewhat  in  detail  they  all  have 
as  a  basis  the  general  idea  that  intermediate  products  are  directly 
concerned  in  the  reactions.  The  writer  wishes  to  discuss  the 
matter  further  in  the  light  of  some  work  done  on  the  urazoles. 
The  experimental  data  of  Berthelot  and  Gilles,9  Menschut- 
kin,10  Goldschmidt,  Ostwald,11  Guldberg  and  Waage,12  Wijs,13 
Knoblauch14  and  Kistiakonsky,15  amply  prove  that  the  sapon- 
ification  of  esters  in  dilute  water  solution  takes  place  according 

to  the  equation, 

% 

-jT      =      Ktran.   X   Cester    X   CffzO  X   Cff. 

What  is  the  mechanism  of  the  reaction?  It  is  well  known 
that  esters  are  weak  bases  and  form  salts  with  acids.  Baeyer16 
and  Villiger  isolated  salts  formed  by  the  union  of  the  esters 
of  acetic,  benzoic  and  oxalic  acids  with  hydroferrocyanic  acid 
and  hydroferricyanic  acid.  Rosenheim17  and  his  students 
proved  that  esters  show  their  basic  properties  by  forming 
double  salts  with  antimony  pentachloride  and  stannic  chloride. 
Walker,  Archibald,  Steele  and  Mclntosh18  showed  that  esters 
unite  with  liquid  hydrochloric  acid  and  form  salts  which  are 

i  Ber.  d.  chem.  Ges.,  34,  1901. 

»  Z.  physik.  Chem.,  36,  405,  663;  40,  501;  47,  356. 

»  See  Mellor's  "Chemical  Statics  and  Dynamics,"  1904,  p.  289. 

*lbid. 

5  Am.  Chem.  J.,  19,  894.     P.  Am.  Assoc.  Adv.  Sci.,  47,  238. 

«  Ber.  d.  chem.  Ges.,  28,  3218;  29,  2208;  39,  711. 

7  Am.  Chem.  J.,  37,  410. 

8  Congress  of  Arts  and  Science,  St.  Louis,  1904,  4,  276. 

9  Ann.  Chim.  Phys.  [3],  65,  385;  [3],  66,  5;  [3],  68,  225;  Compt.rend.,  53,  474,  etc. 
«>  Ann.  Chim.  Phys.  [5],  20,  289;  [5],  23,  14;  [5]   30,  81,  etc. 

»  J.  prakt.  Chem.,  [2],  28,  449. 
«  Ibid.  [2],  19,  82. 

"  Z.  physik.  Chem.,  11,  492;  12,  514. 
"  Ibid.,  22,  268. 
™  Ibid.,  21,  250. 

«  Ber.  d.  chem.  Ges.,  34,  2692,  4189. 
u  Ibid.,  34,  3377;  35,  11 15;  36,  1833  ;  37,  3662 ;  38,  2777. 

«  Z.  physik.  Chem.,  55, 129.   Phil.  Trans.,  205,  99.   J.  Chem.  Soc.,85,  919,  1098; 
87,  784,  1013.     Ber.  d.  chem.  Ges.,  34,  4115.     J.  Am.  Chem.  Soc.,  27,  26;  28,  588. 


dissociated  in  the  liquid  hydrochloric  acid.  They  expressed 
the  opinion  that  the  ester  unites  with  a  hydrogen  ion  and 
forms  a  complex  cathion.  A  large  amount  of  work  on  other 
carbonyl  compounds,  already  referred  to  in  this  paper,  leaves 
no  doubt  that  esters  form  small  quantities  of  salts  in  acid  solu- 
tions, and  the  work  of  Coehn1  on  dimethylpyrone  hydrochloride 
makes  it  probable  that  the  ester  forms  part  of  the  cathion. 
Finally,  the  writer  has  been  able  to  show  that  the  addition 
of  small  quantities  of  methyl  acetate,  ethyl  acetate,  methyl 
benzoate,  i-phenyl-3-ethoxyurazole,  i-phenyl-3,5-diethoxy- 
urazole,  or  benzaldehyde  to  alcoholic  or  aqueous  hydrochloric 
acid  causes  a  lowering  of  the  conductivity  sufficient  to  indicate 
the  formation  of  small  amounts  of  ester  salts  in  solution.  The 
following  table  gives  the  data  obtained: 


Ethyl  acetate 
Methyl  benzoate 
Benzaldehyde 
Benzaldehyde 


•I! 

««£ 
O.I  CC. 

O.I  CC. 
O.I  CC. 
0.2  CC. 


o.i  N    alcoholic  hydro- 
chloric acid  i .  6 

o.  i  N  alcoholic  hydro- 
chloric acid  o .  8 

o.  i  N  alcoholic  hydro- 
chloric acid  5 . 7 

o.i    N    alcoholic    hydro- 
chloric acid  10.0 


Phenyl-3-ethoxyura- 

zole  0.05  gm. 
Phenyl-3-ethoxyura- 

zole  o  .  i    gm. 

Phenyl-3-ethoxyura- 

zole  o  .  5  gm. 
Phenyl-3  ,  5-diethoxy- 

urazole  o.i  gm. 
Phenyl-3  ,  5-diethoxy- 

urazole  o  .  5    gm. 

Methyl  acetate  o  .  i  cc. 

Ethyl  acetate  o  .  i  cc. 

»  Ber.  d.  chem.  Ges.,  35,  2673. 


o.  i  N  hydrobromic  acid 


i.i 


o.i     N    alcoholic    hydro- 
chloric acid  2 . 7 

o.i  N  alcoholic  hydro- 
chloric acid  10.6 

o.i  N  alcoholic  hydro- 
chloric acid  3 . 3 

o.i  N  alcoholic  hydro- 
chloric acid  7 . 9 

o.  i  N  hydrobromic  acid  i .  o 

o.  i  N  hydrobromic  acid  i .  o 


84 

Furthermore,  the  decomposition  of  sulphonic  esters1  and  ura- 
zole  esters2  by  hydrochloric  acid  in  which  ethyl  chloride  is  elim- 
inated, indicates  that  the  esters  form  hydrochlorides. 

The  constitution  of  these  ester  salts  is  a  question  of 
interest.  Many  of  the  workers  in  these  fields  are  of  the  opinion 
that  the  salts  are  derivatives  of  tetravalent  oxygen  and  have 
the  formula  I  and  II. 


Cl 

OH  OH 

RC(C1)OR         RC=O(C1)R 


III. 


H 


H 
C6H5N NCI 

I  II 

OC  COR 

\   / 
NCH3 

VII. 


Since  many  esters  and  hydrochloric  acid  yield  ethyl  chloride 
formulas  III.  and  IV.  should  also  be  considered  and  all  four  may 
be  in  tautomeric  equilibrium.  The  urazole  ester  hydro- 
chlorides  may  also  exist  in  the  form,  V.,  VI.,  VII.  and  VIII. 
in  equilibrium,  with  some  one  or  two  forms  in  preponderance. 

Since  the  esters  then  form  salts  it  might  be  at  once  suspected 
that  in  the  saponification  of  esters  by  water  in  the  presence  of 
acids  the  ester  cathion  is  saponified,  just  as  the  alkyl  halides 

»  Am.  Chem.  J.,  19,  894. 

2  Acree    and  collaborators:  Am.  Chem.  J.,  27,118;   31,185;  32,606;  37,71,  361; 
88,  1.    Ber.  d.  cbem  Ges.,  35,  553;  36,  3139;  37,  184,  618. 


85 

react  with  anions,  and  acetamide  cathions  and  imido  ester 
cathions  are  hydrolyzed.  Buler,  Bredig,1  Lap  worth,  Stieg- 
litz,  and  Acree  and  Johnson  have  held  that  view,  and  many 
of  the  following  equations  have  been  developed  by  these  writers, 
especially  by  Stieglitz.  The  equations  are  given  here  again, 
with  others,  to  develop  the  entire  subject. 

If  Cest  gram  molecules  of  ester  and  enough  hydrochloric 
acid  to  give  CH  gram  ions  of  hydrogen  ions  are  brought  to- 
gether in  i  liter  of  water  we  shall  have  the  following  reaction 
established  very  quickly,  and  get  the  equation 

CH3COOR  +  H    ^    CH3COOR.H 

(Cest  —  y)(Cff—  y)      =      j~y      =      ~CSaltdiS,  (2) 

in  which  y  is  the  very  small  amount  of  salt  formed ;  the  hydro- 
gen ions  from  the  water  and  small  non-dissociated  portions 
of  the  ester  salt  are  disregarded.  If  now  the  ester  cathion  is 
the  substance  hydrolyzed,  we  shall  have,  if  we  disregard  the 
very  small  reverse  reaction, 

CH3COOR.H  -f  H2O    "±    CH3COOH  +  ROH  +  H 


— ^ —  =     KtransCsalt  dis  X  CfftO>  (3) 

When  the  formation  of  the  salt  from  the  ester  and  hydrogen 
ions  takes  place  very  rapidly  in  comparison  with  the  saponi- 
fication  of  the  ester  cathion,  and  the  value  of  y  is  negligible 
in  comparison  with  Cest  and  CH  we  can  substitute  for  C5alt  dis 

TV" 

in  equation  (3)  the  value-^—  Cest  X  CH  and  we  then  get,  as 
has  been  developed  before  in  the  other  sections, 

dC salt  dis  dx  Ktrans^b  ,  ~  \  s^        /  s /^  \         /-    x 

~dt~        =Ht~~      — K^ — (Ccst~  *)c"X(C/,2o— *),     (4) 
which  is  only  another  form  of  equation  (i).     This  equation 

1  Z.  Elek.  Chem.,  9,  118;  10,  586;  11,  528. 


86 

seems  to  hold  whether  the  hydrogen  ions  come  from  water,. 
weak  acids  or  stronger  acids.  We  have  then  harmony  between 
the  quantitative  data  and  the  idea  that  the  ester  cathion  may 
be  the  substance  hydrolyzed.  The  ester  exists  in  solution  prob- 
ably only  as  free  base,  cathions  and  undissociated  salt.  The 
free  base  is  hydrolyzed  certainly  only  very  slowly  by  the  water 
as  direct  experiment  shows.  If  the  undissociated  ester 
hydroctiloride  were  the  substance  chiefly  hydrolyzed  we  should 
have,  as  has  been  developed  in  the  previous  sections,  the  fol- 
lowing equation  expressing  the  reaction  velocity: 


Since  the  velocity  of  hydrolysis  of  esters  is  not  proportional 
to  the  square  of  the  concentration  of  the  hydrogen  ions,  it  is 
evident  that  the  non-dissociated  ester  salt  can  not  be  greatly 
concerned  in  the  saponification.  Furthermore,  since  the  free 
ester  is  not  appreciably  concerned  in  the  reaction  there  is  left 
only  the  ester  cathions,  and  this  seems  to  be  the  substance 
which  is  really  hydrolyzed.  But  the  moment  the  hydrolysis 
of  the  ester  begins  the  reverse  reaction,  the  formation  of  the 
ester  from  the  organic  acid  and  the  alcohol  also  begins. 

The  reactions  involved  in  formation  of  esters  from  organic 
acids  and  alcohols  in  the  presence  of  hydrogen  ions  are  probably 
exactly  analogous  to  those  involved  in  the  saponification 
of  the  esters.  Lapworth,  Euler,  Kastle,  and  Stieglitz  have 
pointed  out  that  the  organic  acids  probably  unite  with  the 
hydrogen  ions  to  a  small  extent  and  that  this  complex  organic 
acid  cathion  reacts  with  the  alcohol  and  forms  the  ester,  water 
and  hydrogen  ions.  There  is  no  doubt  that  the  organic  acids 
do  have  weakly  basic  properties,  just  as  many  ureas,  pyrimi- 
dines,  urazoles  and  amides  have  both  basic  and  acid  properties. 
Rosenheim1  found  that  organic  acids  behave  like  the  esters 
in  their  action  on  antimony  pentachloride.  Hell  and  Muhl- 
hauser2  found  that  acetic  and  other  organic  acids  form  unstable 

1  Lac.  cit. 

*  Ber.  d.  chem.  Ges.,  12,  734 


87 

hydrobromides,  such  as  2CH3COOH.HBr.  Mclntosh1  observed 
similar  phenomena  and  Farmer2  showed,  too,  that  organic  acids 
have  basic  properties. 

If,  then,  the  organic  acid  does  actually  unite  with  the 
hydrogen  ions  and  form  a  cathion,  which  reacts  with  the  alco- 
hol, we  shall  have  the  following  equation  holding  under 

CH3COOH  +  H     *i     CH3COOH.H 


K.  K 

(  Cacid  —  y )  ( CH  —  y )       =      -j^r  X      —      JsT  Cacid  salt  dis  ,       (6) 

/V   A  /V  A 

exactly  the  same  conditions  which  apply  to  the  ester.  K'A  is 
the  affinity  constant  of  the  acetic  acid  as  above,  and  y'  is  the 
small  amount  of  cathion  formed,  the  molecular  form  of  the 
salt  being  so  small  in  amount  as  to  be  disregarded. 

If  the  acid  cathion  is  the  substance  which  reacts  with  the  al- 
cohol we  shall  have,  if  we  again  disregard  the  small  amount 
of  the  reverse  reaction, 

CH3COOH.H  +  ROH     Tt     CH3COOR  +  H2O  +  H 


dC  acid  salt  dis       __  VI          r  \^t    r>  f *\ 

—r. —   —   — -ft-  trans^-  acid  salt  dis  X  ^-alc-  W  ) 

at 

But  just  as  with  the  esters  we  can  substitute   for  Cacidsaltdis 

K' 
in  (7)  the  value-v^—  Cadd  X  C&.     We  then  get,  as  developed 

-tv-Zf 

with   the   esters,    equation    (8)    as   representing 

-^       =      ^ trans—  (Cacid  —  *)   X    (Calc  —  X)   X   CHt       (8) 

the  reaction  which  should  be  found  to  hold  experimentally 

if  the  organic  acid  first  unites  very  rapidly  with  the  hydrogen 

+ 

ions  and  forms  a  complex  cathion,  CH3COOH.H,  which  reacts 
slowly  with  the  alcohol  and  forms  ester,  water  and  hydrogen 
ions.  Equation  (8)  is  actually  found  to  represent  the  velocity 

i  J.  Am.  Chem.  Soc.,  28,  588. 
«  J.  Chem.  Soc.,  83,  1440. 


88 

of  formation  of  the  esters.  We  are  led,  then,  to  the  idea  that 
the  reversible  reactions  in  the  system,  water,  alcohol,  ester, 
organic  acid  and  hydrochloric  acid  are  brought  about  by  the 
formation  and  reactions  of  intermediate  cathions  produced  by 
the  union  of  hydrogen  ions  with  the  ester  and  organic  acid. 

Whether  the  acid  cathion,  CH3COOH.H,  has  the  formula  IX., 
X.  or  XI.  need  not  be  discussed. 

H 
6 

CH3C(O)OH  CH3C(OH)2  CH3C=OH 

H 
IX.  x.  XI. 

When  the  system  is  in  equilibrium  just  as  much  ester  is  formed  as 
is  saponified  into  organic  acid.  The  two  terms  dx  in  equations 
(4)  and  (8)  are,  therefore,  equal  and  we  get,  by  substitution, 
equation  (9)  as  representing  the  equilibrium  conditions. 

K  K! 

K-trans~r^~Cest   X   Cff2Q  X    Cff  =    K.  trans  ~T? Cacid    X  Calc  X   Cff 
&.w  A.* 

or 

Q,est  X   KCff^o      —      K-'Cacid  X  Cale*  (9) 


cadd  and  caic  are  the  concentrations  of  thes- 
substances  at  the  equilibrium  point.  C^  is  the  original  cone 
centration  of  the  hydrogen  ions  less  the  very  small  amount 
united  with  the  ester  and  organic  acid.  The  equilibrium 
point  is  apparently  independent  of  the  concentration  of  the 
hydrogen  ions. 

To  recapitulate  then :  The  idea  that  the  reversible  reactions 
taking  place  in  the  system  ester,  water,  acid,  alcohol  and  hydro- 
chloric acid  are  due  to  reactions  of  the  complex  cathions,  formed 
by  the  union  of  a  very  small  amount  of  the  hydrogen  ions  with  a 
small  amount  of  the  ester  and  organic  acid,  leads  to  equations 
which  hold  experimentally.  The  assumption  explains,  in 
equations  (4)  and  (8),  why  the  velocity  of  saponification  and 
of  esterification  increases  directly  in  proportion  to  the  con- 
centration of  the  hydrogen  ions.  It  further  makes  clear,  in 


89 

equation  (9),  the  experimentally  established  fact  that  the  equi- 
librium of  the  system  is  not  appreciably  changed  by  change 
in  the  concentration  of  the  hydrogen  ions.  These  ideas  have 
already  been  developed  by  Buler,  Lap  worth,  Kastle  and  es- 
pecially by  Stieglitz,  and  they  have  received  very  good  experi- 
mental verification.  Goldschmidt1  has  recently  pointed  out 
some  discrepancies  not  entirely  in  harmony  with  the  above 
equations  and  doubtless  many  others  will  be  reported  later. 
The  assumption,  however,  gives  a  good  working  basis  and  may 
be  used  as  a  guide  for  the  further  work  needed  to  clear  up  the 
whole  matter.  There  is  one  very  serious  objection  to  an  assump- 
tion common  to  the  ideas  advanced  by  Buler,  Zengelis  and 
Lapworth.  Lapworth  proposed  the  idea  that  the  organic 
acid  unites  with  the  hydrogen  ion, 

X)H 

CH8COOH  +,H  ,;*JJ    CH8C—       '  (i) 

\OH 

and  that  this  product  then  reacts  with  the  alcoholate  ion  as 
follows  : 


xOH  ,OH 

CH3C—        +C2HS0     ^    CH8C—  OC2H5     ^ 

\)H  \OH 

CH3COOCaH5  +  H20     (2) 

The  objection  is  the  following:  The  increase  in  the  concen- 
tration of  the  hydrogen  ions  in  the  solution  of  the  organic 
acid  and  alcohol  to  n  times  its  former  value  would,  it  is  true, 
cause  the  concentration  of  the  organic  acid  cathion  in  equa- 
tion (i)  to  become  approximately  n  times  as  great;  if  the 
concentration  of  the  alcoholate  ions  in  (2)  were  to  remain  the 
same  then  the  reaction  velocity  would  become  n  times  its  former 
value.  But  if  the  alcoholate  ions  come  from  the  dissociation 
of  the  alcohol  according  to  equation  (3) 

1  Goldschmidt  and  Sunde:  Ber.  d.  chem.  Ges.,  39,  711. 


90 
C2H5OH    *£    C2H50  +  H  (3) 


the  increase  of  the  H  concentration  to  n  times  its  former  value 

would  cause  the  concentration  of  the  C2H5O  ions  to  become 

the  nth  part  of  its  former  value.  The  product  of  the  alcoholate 

+ 
ions  C2H5O,  and  the   organic    acid    cathions    CH3C(OH)2    in 

(2)  would,  therefore,  not  be  changed  at  all  and  the  reaction 
velocity,  if  Lap  worth's  explanation  were  correct,  would  remain 
unchanged  with  change  in  the  concentration  of  the  hydrogen 
ions.  The  same  thing  would  hold  true  of  the  reverse  reaction 
expressed  as  follows, 

+/OC2H6 
CH3COOC2H6  +  H     ^     CH3C—  (4) 


followed  by  the  reactions  in  equation  (5). 

/OC2H5  ,OH 

CH3C—  +  OH     ^     CH3C— OC2H5 


CH3COOH  +  C2H5OH     (5) 

Although  an  increase  in  the  concentration  of  the  hydrogen 
ions  to  n  times  a  former  value  would  cause  the  concentration 
of  the  ester  cathion  in  (4)  to  become  n  times  as  great,  yet  this 
same  increase  in  the  concentration  of  the  hydrogen  ions  would 
cause  the  concentration  of  the  hydroxyl  ions  in  (5)  to  become 
the  wth  part  of  its  former  value,  and  hence  the  velocity  of  the 
reaction  would  be  independent  of  the  concentration  of  the 
hydrogen  ions.  The  same  objection  holds  for  certain  assump- 
tions made  by  Euler  and  Zengelis  and  these  will  be  discussed 
later.  Especially,  however,  must  it  be  emphasized  that  the 

assumption  of  the  ionization  of  acetic  acid  into  acetyl  and  hy- 

+  — 

droxyl  ions  and  CH3CO,  OH,  and  of  alcohol  into  ethyl  and  hy- 

+ 
droxyl  ions,  C2H5  and  OH,  fails  to  meet  the  requirements  of 

the  mass  law  in  the  reactions  under  consideration.     It  is  clear 


then  that  the  alcohol  and  water  react  with  the  acid  cathion 
and  the  ester  cathion  not  as  ions  but  as  neutral  molecules, 
just  as  the  neutral  ethyl  iodide  reacts  with  urazole  ions,  hydroxyl 
ions,  etc.  The  water  or  alcohol  is  probably  added  to  the  carbonyl 
group  in  these  reactions,  but  this  is  not  certain. 

/OH 

,.  +H20     »->•     CH3C—  OH      ~+ 

OC2H5  \+ 

H  UU2±i5 

H 
CH3COOH  +  H  +  C^OH     (6) 

>  /OH 

+ROH     ^     CH3C—  OR 


H 
O 

II  + 

CH3C  —  R  +  H20-f-H     (7) 

In  the  saponification  of  esters  and  amides  by  alkalies  the  al- 
kali probably  attacks  the  carbonyl  group.  Euler1  and  others 
referred  to  above  have  shown  that  carbonyl  compounds,  such 
as  aldehydes,  have  both  basic  and  acid  properties. 

CH3COOR  +  K  +  OH  +  H2O    »-*• 


CH3C— OH       +  K  +  H2O 
\OC2H5 


CH3COO  +  ROH  +  K  +  H,O     (8) 


>  +       - 

+  K  +  OH  +  H2O 
NH2 

Ber.  d.  chem.  Ges.,  38,  2551 ;  39,  344. 


92 


CH3C— OH    +  K  +  H2O 


CH3COO  +  K  +  NH3  +  H20     (9) 

In  the  consideration  of  the  hydrolysis  and  the  formation  of 
ordinary  esters  one  phase  of  the  work  does  not  apply,  but  it 
must  be  developed  for  other  esters. 

Although  the  hydrochlorides  of  the  ordinary  esters  do  not 
decompose  appreciably  into  the  alkyl  chlorides  and  the  organic 
acids,  some  ester  hydrochlorides  do  suffer  this  transformation 
along  with  the  hydrolysis.  A  notable  case  is  that  of  the  sul- 
phonic  esters.  When  a  sulphonic  ester  is  treated  with  water 
and  hydrochloric  acid,  two  apparently  independent  side  reac- 
tions take  place.  One  is  the  hydrolysis  of  the  ester  into  the 
sulphonic  acid  and  the  alcohol  corresponding,  and  the  other  is 
the  decomposition  of  the  sulphonic  ester  hydrochloride  into 
the  alkyl  chloride  and  the  sulphonic  acid.1 

I.  C6H6S03C2H6  +  H  +  Cl  +  H20    ^ 

C6H5S03C2H6.H  -f  H20  +  Cl     »-*• 

CeH5SO3H  +  C2H5OH  +  H  +  Cl. 

II.  C,H6SO3C2H5  +  H  -f  Cl  !£1  C6H5SO3C2H5.HC1  »-*- 

C6H5S03H  +  C2H5C1. 

Evidently  the  amount  of  transformation  through  each  of 
the  reactions  I.  and  II.  depends  upon  the  relative  stability  of 
the  sulphonic  ester  cathion  towards  water  and  the  stability 
of  the  sulphonic  ester  hydrochloride.  These  2  factors  will 
doubtless  vary  with  the  ester,  temperature  and  other  condi- 
tions. Apparently,  it  should  be  possible  to  suppress  the  re- 
action I.  and  give  reaction  II.  more  opportunity  to  become  the 
chief  one  by  treating  the  sulphonic  ester  in  alcoholic  hydro- 
chloric acid.  This  has  been  done  with  certain  urazole  deriva- 
tives. 

*  Kastle  and  Ftazer:  Am.  Chem.  J.,  19,  894. 


93 

We  should  then  expect  to  find  some  esters,  the  cathions  of 
which  are  so  stable  towards  water  that  the  esters  would  hardly 
undergo  hydrolysis  at  all,  but  the  hydrochlorides  of  which 
might  easily  decompose  into  the  acids  and  an  alkyl  chloride. 
Such  esters  are  those  of  the  urazoles.  A  brief  account  of  their 
properties  will  be  given  here,  and  a  more  detailed  statement 
will  be  made  later. 

The  i-phenyl-3-ethoxyurazole  is  not  saponified  by  aqueous 
hydrobromic  acid,  but  is  decomposed  quantitatively  by  alcoholic 
hydrochloric  acid  into  phenylurazole  and  ethyl  chloride.  Five 
cc.  0.0992  N  hydrobromic  acid  and  o.i  gram  phenyl-3-ethoxy- 
urazole  were  heated  12  hours,  at  100°.  The  solution  then  ti- 
trated against  5.00  cc.  0.0995  N  potassium  hydroxide  in  the 
presence  of  methyl  orange  and  10.00  cc.  0.0995  N  potassium 
hydroxide  in  the  presence  of  phenolphthalein.  This  shows 
that  no  hydrobromic  acid  was  used  in  the  formation  of  ethyl 
bromide  and  phenylurazole.  The  solution  was  acidified  with 
sulphuric  acid  and  extracted  with  chloroform.  No  phenyl- 
urazole was  obtained,  but  when  the  chloroform  filtrate  was  evap- 
orated, o.i  gram  of  i-phenyl-3-ethoxyurazole,  m.  p.  148°, 
was  recovered.  In  order  to  study  the  reaction  quantitatively 
we  used  the  i-phenyl-3,5-diethoxyurazole  and  alcoholic  hydro- 
chloric acid  in  equimolecular  quantities  in  0.5  N  solutions. 

C6H5N N 

I  II 

C2H5OC  COC2H5. 

%  / 

N 

Since  the  2,3-amide  group  is  a  much  stronger  acid  than  the 
4,5-amide  group  it  was  predicted  that  the  5-ethoxy  group  would 
be  a  very  much  stronger  base  than  the  3-ethoxy  group  and 
would  unite  with,  and  react  with,  the  hydrochloric  acid  nearly 
to  the  exclusion  of  the  3-ethoxy  group.  This  prediction  was 
happily  verified  quantitatively  by  experiment.  The  reactions 
were  carried  out  in  small  sealed  tubes  at  60  °,  and  after  the  reaction 
was  stopped  the  contents  were  poured  into  water  in  extraction 
funnels.  The  unchanged  hydrochloric  acid  was  titrated  with 
standard  alkali  in  the  presence  of  methyl  orange  and  the  i- 


94 

phenyl-3-ethoxyurazole  formed  was  then  titrated  with  stand- 
ard alkali  in  the  presence  of  phenolphthalein.  The  unchanged 
i-phenyl-3,5-diethoxyurazole  was  extracted  by  means  of 
chloroform  and  weighed. 

If  the  urazole  ester  hydrochloride  is  decomposed  directly 
we  should  have  the  reaction  expressed  by  the  following  equa- 
tions: 

i  ci 

ROC2H6  +  H  +  Cl  T±  R—  O—  C2H5  *^    ROH  +  C2H5C1. 

H 

-  -J-.  -       =       KtransCesthclt  C1) 

at 

in  which  Cest  hcl  is  the  concentration  of  the  urazole  ester  hydro- 
chloride  at  any  moment.  But  the  concentration  of  the  ester  hy- 
drochloride can  be  expressed  approximately,  as  has  been  de- 
veloped several  times  above,  in  terms  of  the  concentrations  of 
the  ester,  hydrogen  ions  and  chloride  ions  at  any  moment 
and  can  be  represented  by  the  equation 

Cl 

R  —  OC2H6. 
H 


est  Hcl, 


(2) 


in  which  (C^  —  x),  (Ccl — x)  and  CH  are  the  concentrations  of 
the  ester,  chloride  ions  and  hydrogen  ions  at  any  moment.  We 
can,  therefore,  substitute  for  Cesthcl  in  (i)  its  value  in  (2)  and 
we  then  get  equation  (3) 

dx 


dt  dt 

Ktrans 


•rr-  -rr  \  •«-»  CSl 

Baffin  •*»•«/ 

-x)CH.    (3) 


This  equation  will  not  hold  exactly  since  the  value  of  CH.  does 
not  remain  contant  as  indicated  in  (3)  but  decreases  to  some 
extent  because  the  urazole  acid  formed  is  weaker  than  hydro- 


95 

chloric  acid.  We  should  expect  the  value  of  K  to  decrease, 
and  if  the  urazole  acid  formed  were  very  weak,  equation  (3) 
would  become  practically  trimolecular. 

The  following  data,  however,  show,  qualitatively,  that  the 
urazole  ester  actually  does  act  upon  the  hydrochloric  acid  and 
form  ethyl  chloride.  The  experiments  are  given  in  a  tabu- 
lar form  for  convenience. 

Time  in  minutes.  x.  A.  —  X. 

15  0.528  0.472 

32  o . 706  o . 294 

6O  O.74I  O.259 

180  0.913  0.087 

Average,     0.064 

As  a  consequence  of  this  decomposition  of  the  ester  hydro- 
chloride  it  has  been  impossible,  as  was  predicted,  to  obtain 
the  esters  by  heating  the  urazole  acids  with  alcoholic  hydro- 
chloric acid. 

This  work  on  the  urazole  esters  and  sulphonic  esters  will 
be  continued. 

The  discussion  of  the  reversible  reaction  between  esters, 
water,  alcohol  and  organic  acid  has  led  to  an  understanding 
as  to  why  the  three  so-called  laws1  of  catalysis  apply  to  this 
particular  *case.  These  laws  may  be  expressed  as  follows : 

(1)  When  the  catalyzer  is  not  changed  during  the  reaction  it 
affects  only  the  'velocity  of  the  reaction,  but  does  not  change  the 
nature  of  the  reaction  or  the  apparent  order  of  the  reaction. 

(2)  The  catalyzer  affects  the  velocity  constant  directly  in  pro- 
portion to  the  concentration  of  the  catalyzer. 

(5)  A  change  in  the  concentration  of  the  catalyzer  does  not 
change  the  equilibrium  point  in  reversible  reactions. 

These  three^so-called  laws  have  been  found  to  hold  so  well  for 
the  esterification  work  that  they  have  been  assumed  to  hold 
for  all  catalytic  reactions.  The  esterification  work,  the  hy- 
drolysis of  amides,  and  the  inversion  of  cane-sugar  are  prac- 

1  For  an  excellent  discussion  of  catalysis  see  Herz  "Die  Lehre  von  der  Reaktions- 
eschleunijzung  durch  Fremdstoffe,"  Ahren's  Sammlung,  Vol.  XI,  p.  103. 


96 

tically  the  only  well-known  cases  in  which  a  catalytic  reac- 
tion has  been  well  studied,  and  it  is  rather  surprising  that 
these  three  cases  should  be  the  basis  of  the  above  so-called  laws. 
It  will  now  be  shown  that  these  so-called  laws  are  not  laws  at 
all,  but  apply  only  to  certain  special  cases,  and  further  that 
these  so-called  laws  have  no  physical  or  chemical  basis  but 
are  really  only  a  brief  statement  of  the  results  actually  obtained 
experimentally.  They  cannot  be  used  to  make  predictions 
concerning  all  catalytic  reactions,  but  are  only  approximate 
expressions  of  special  reactions. 

There  are  two  classes  of  reactions  that  must  be  considered 
in  showing  that  these  laws  for  catalysis  by  acids  (or  bases) 
do  not  hold:  (i)  (A)  Simple  reactions  in  which  one  reaction 
constituent  is  a  strong  base  (or  acid),  and  (B)  reversible  re- 
actions in  which  a  constituent  of  one  reacting  set  of  the  sub- 
stances is  a  much  stronger  base  (or  acid)  than  the  correspond- 
ing base  (or  acid)  in  the  opposing  set  of  substances.  (2)  (A) 
Simple  reactions  in  which  the  catalyzer  affects  the  reaction 
velocity  in  proportion  to  the  square,  or  other  power  of  its  con- 
centration, and  (B)  reversible  reactions  in  which  the  velocity 
of  one  reaction  increases  as  the  m  power  of  the  concentration 
of  the  catalyzer  increases,  while  the  velocity  of  the  reverse 
reaction  increases  in  proportion  to  the  m  power  of  the  concen- 
tration of  the  catalyzer.  These  cases  will  be  considered  in  the 
order  given. 

(i)  If  in  a  reaction  one  of  the  constituents  is  a  compara- 
tively strong  base,  such  as  ammonia,  aniline,  etc.,  and  it  enters 
into  the  reaction  through  the  reaction  of  its  cathion  with  the 
other  constituents,  then  the  velocity  of  the  total  reaction  can- 
not increase  directly  in  proportion  to  the  increase  in  the  con- 
centration of  the  hydrogen  ions  added.  The  consideration 
of  the  hydrolysis  of  cane-sugar  will  make  this  clear.  In  the 
hydrolysis  of  cane-sugar  according  to  the  following  equation, 
the  amount  of  hydrogen 

(C.HU06)20  +  H20  +  H  +  Cl    ^ 

(C6HU06)2OH  H-  H20  +  Cl    «-*• 

2C.HU0.  +  H  +  C1. 

(Csuf-yXCff-y)     =    KCsugcatt  (i) 


97 

ions  and  of  cane-sugar  used  to  form  the  cane-sugar  cathion  is 
so  small  that  the  concentrations  of  these  two  are  hardly  affected, 
and  (CH — y)  and  CH  are  practically  equal.  It  follows,  then, 
that  if  the  concentration  of  the  hydrogen  ions  added  were 
made  twice  as  great  the  (2CH — y')  corresponding  to  the 
new  conditions  would  be  practically  twice  as  great  as  before, 
and  the  new  value  of  Csufcaf  would  also  be  twice  as  great 
as  before.  The  velocity  of  the  reaction  would  then  be  twice 
as  great,  as  we  actually  find  by  experience. 

Suppose,  however,  that,  even  though  the  sugar  did  not  re- 
act appreciably  with  water  and  form  a  cathion  of  the  corre- 
sponding base  (ammonia  and  aniline  are  such  cases),  it  could 
unite  almost  completely  with  a  molecular  quantity  of  hydro- 
chloric acid,  just  as  ammonia  and  aniline  do.  Then  the  addi- 
tion of  a  quantity  of  hydrochloric  acid  equivalent  to  one-fourth 
of  the  cane-sugar  would  cause  one-fourth  of  the  cane-sugar  to 
be  changed  into  the  corresponding  cathions  and  the  reaction 
velocity  would  have  a  certain  value.  The  addition  of  twice 
the  amount  of  hydrochloric  acid  would  cause  nearly  half  of 
the  cane-sugar  to  be  changed  into  cathion  and  the  velocity 
constant  would  become  nearly  twice  a^s  great  as  before.  The 
addition  of  one  molecular  quantity  of  hydrochloric  acid  would 
cause  the  concentration  of  the  sugar  cathion  and  the  velocity 
constant  to  become  nearly  four  times  the  former  value. 
Up  to  this  point,  then,  the  velocity  constant  would  increase 
nearly  directly  in  proportion  to  the  increase  in  the  amount 
of  hydrochloric  acid  added.  But  the  further  addition  of  hy- 
drochloric acid  would  not  cause  the  corresponding  increase 
in  the  velocity  constant,  because  the  cane-sugar  would  be  al- 
ready nearly  completely  converted  into  cathions  arid  the  fur- 
ther addition  of  hydrochloric  acid  would  cause  only  a  slight 
increase  in  the  concentration  of  the  cathions.  In  fact,  the  ad- 
dition of  much  hydrochloric  acid  would  cause  a  suppression  of 
the  ionization  of  the  cane-sugar  hydrochloride  and  hence  a 
decrease  in  the  concentration  of  the  cathions  and  the  velocity 
constant  of  the  reaction.  It  is  evident,  then,  that  if  one  of 
the  reacting  constituents  is  a  fairly  strong  base  which  enters 
into  the  reaction  through  its  cathions  the  velocity  of  the  re- 


98 

action  cannot  increase  directly  in  proportion  to  the  concentra- 
tion of  the  acid  added.  Examples  of  this  are  the  reactions 
between  carbonyl  compounds  and  hydroxylamine,  the  hy- 
drolysis of  amides  by  aqueous  solutions  of  acids,  and  the  hy- 
drolysis of  imido  esters  by  acids.  Under  these  conditions 
the  second  law  of  catalysis  cannot  hold.  It  can  hold  only 
in  those  cases  in  which  the  base  is  so  weak  that  only  a  trace 
of  the  salt  is  formed;  since  these  are  the  only  cases  studied 
up  to  this  time  it  is  not  surprising  that  not  much  further  thought 
was  given  to  the  matter. 

(2)  The  third  law  of  catalysis  cannot  hold  in  those  reversible 
reactions  in  which  one  constituent  of  one  reaction  is  a  strong 
base,  while  the  corresponding  constituent  of  the  reverse  re- 
action is  a  very  weak  base,  provided  the  bases  enter  into  the 
reactions  through  their  cathions  or  salts.  This  has  already 
been  discussed  in  the  reversible  reactions  between  carbonyl 
compounds  and  hydroxylamine  and  its  hydrochloride.  These 
reactions  are  accelerated  by  the  addition  of  hydrochloric  acid. 

(CH3)2CO  +  NH2OH  +  H  ^  (CH3)2CO  +  NH3OH 

(CH3)2C  -  NHOH  +  H20  Tt  (CH3)2C  -  NOH  +  H. 


The  acetoxime  is  a  very  weak  base  and  hence  unites  with 
only  a  small  part  of  the  acid  when  one  molecular  quantity  of 
hydrochloric  acid  is  added.  The  addition  of  two  molecular 
quantities  of  hydrochloric  acid  would  cause  the  formation  of 
nearly  twice  as  much  acetoxime  cathion  and  hence  the  velocity 
of  the  hydrolysis  of  the  acetoxime  cathion  should  be  nearly 
twice  as  great.  But  the  addition  of  one  molecular  quantity 
of  acid  to  the  hydroxylamine  changes  the  hydroxylamine 
practically  completely  into  the  hydroxylammonium  ions,  and 
the  addition  of  two  molecular  quantities  of  acid  would  hardly 
change  the  concentration  of  the  hydroxylammonium  ions. 
It  is  evident,  then,  that  the  equilibrium  in  the  system  given 
above  would  be  changed  by  the  addition  of  more  acid.  Know- 
ing that  the  acetoxime  is  the  weak  base,  we  could  predict 
that  the  addition  of  more  acid  would  cause  the  formation  of 
more  acetoxime  cathion  from  the  acetoxime  then  in  solution 


99 

but  would  cause  no  further  appreciable  formation  of  hydroxyl- 
ammonium  ions  from  the  hydroxylamine  then  in  solution. 
As  a  result,  because  of  the  equilibrium  between  the  water  and 
acetoxime  cathions  on  the  one  hand  and  the  acetone  and  hy- 
droxylammonium  ions  on  the  other  the  addition  of  more 
acid  causes  a  change  in  the  equilibrium  of  the  system  and 
results  in  the  formation  of  more  of  the  hydroxylammonium 
ions,  or  ions  corresponding  to  the  stronger  base. 

(3)  The  second  law  of  catalysis  cannot  hold  in  those  reac- 
tions in  which  changes  are  brought  about  by  the  union  of  very 
small  amounts  of  two,  three,  or  more  ions,  or  molecules,  of  the  cat- 
alyzing agent  with  a  very  small  amount  of  some  compound  in 
the  reaction  system,  which  addition  product  then  reacts  with 
other  constituents.  This  case  has  already  been  considered 
in  the  rearrangement  of  the  acetylhalogenaminobenzene  de- 
rivatives, into  halogenacetanilide  derivatives,  where  it 
was  shown  that  the  velocity  of  this  catalyzed  reaction  in- 
creases as  the  square  of  the  concentration  of  the  hydrogen 
ions  instead  of  as  the  first  power  demanded  by  the  second 
law  of  catalysis.  We  can  readily  see  that  in  some  reactions 
involving  some  reaction  similar  to  a  hydrolysis  we  might 
have  two,  three  or  more  ions,  or  molecules  of  the  catalyzeruniting 
with  some  constituent  and  the  further  transformation  of  this 
addition  product  into  other  substances.  The  following  equa- 
tions will  give  some  types  of  these  reactions : 

+        — 

ATJrr^l      -r*  ._•>       T>     i     TT     i     pi . 
.jnv^i     *••  ~~*      jj  -j-  xi.  -f-  v^i, 

(2)  A  -f  2H     7^     A.2H     «-*-     B  +  2H; 

(3)  A  +  2H  +  Cl     *t     A.H2C1     m+     B  +  2H  +  Cl; 


(4)   A  +  2H  +  2C1  +  B 


A.2HC1  -f  B     »->-     C  +  2H  +  2C1; 


(5)  A  +  4Cat  +  B     ^     A.4Cat  +  B     »->-     C 
The  first  two  reactions  will  increase  in  velocity  directly  in 


100 

proportion  to  the  square  of  the  concentration  of  the  hydrogen 
ions,  the  velocity  of  the  third  reaction  will  increase  in  propor- 
tion to  the  third  power  of  the  concentration  of  the  hydrogen 
ions  and  the  velocity  of  the  fourth  and  fifth  reactions  will 
increase  in  proportion  to  the  fourth  power  of  the  concentra- 
tion of  the  hydrogen  ions  or  catalyzer. 

(4)  The  third  law  of  catalysis  cannot  hold  in  those  reversi- 
ble reactions  in  which  the  velocity  of  one  reaction  is  accelerated 
in  proportion  to  the  m  power  of  the  concentration  of  the  cata- 
lyzer while  the  velocity  of  the  reverse  reaction  is  accelerated 
in  proportion  to  the  n  power  of  the  concentration  of  the  cata- 
lyzer. It  is  assumed,  here,  as  in  (3),  that  only  very  small 
amounts  of  the  catalyzer  unite  with  very  small  amounts  of 
some  other  substance  and  that  the  addition  product  then  under- 
goes further  transformation. 

As  an  illustration  let  us  consider  the  following  equations: 


A.wH-fB     »-»     C-f-D  +  wH      (i) 


and 


+  D  +  nH     *±     C.nH  +  D     »->-     A  +  B  +  nH.      (2) 


The  velocity  of  the  reaction  can  be  represented  by  the  equa- 
tion  (3) 

—K'(Cc  +  x)(CD  +  x)CnH.  (3) 


When  equilibrium  is  established  we  have 
*)CJJ    =     K'(CC 


or 

K(CA-xKC*-x)  C^ 

K'(Cc+x((CD+x)  CmH 

There    was    a    mistake    on    page    412    in    the    article1    by 

m 

Acree  and  Johnson  in  that  the  term  (Ccat)n   was  by  an  over- 

»  Am.  Chem.  J.,  87,  410. 


IOI 

sight  inserted  instead  of  the  expression  C%^n.  Since  C*£~m 
in  (4)  varies  with  the  change  in  the  concentration  of  the  hy- 
drogen ions  it  is  evident  that  the  equilibrium  between  A,  B,  C 
and  D  must  vary  with  the  change  in  the  concentration  of  the 
ions.  In  the  work  on  esters  n — m  becomes  zero  and  CJ^"*1  be- 
comes unity,  and  the  equilibrium  is  not  appreciably  changed 
by  a  change  in  the  concentration  of  the  catalyzer.  It  is  evi- 
dent that  when  n  and  m  are  equal,  but  not  unity,  the  third 
law  of  catalysis  holds,  but  the  second  does  not. 

The  discussion  in  the  preceding  sections  applies  equally 
well  to  the  reactions  in  which  negative  catalysis  takes  place. 
It  is  perfectly  evident  that  the  velocity  of  certain  reactions, 
reversible  or  non-reversible,  could  be  decreased  because  the 
catalyzer  combines  with  some  constituent  of  the  reacting  sys- 
tem and  hence  causes  a  decrease  in  the  concentration  of  that 
constituent.  The  conditions  for  negative  catalysis  would  be 
fulfilled  if  the  addition  product  does  not  react  directly  with 
the  other  constituents,  but  is  always  in  equilibrium  with  the 
catalyzer  and  the  other  component  of  the  addition  product, 
which  component  does  react  with  the  other  constituents. 
The  negative  catalysis  of  the  reaction  between  the  phenyl- 
thiourazole  anion  and  ethyl  iodide  by  the  hydrogen  ions  of 
hydrochloric  acid  is  a  very  good  example.  The  hydrogen 
ions  unite  with  some  of  the  phenylthiourazole  anions,  decrease 
the  concentration  of  the  phenylthiourazole  anions  and  hence 
lower  the  velocity  of  the  reaction.  Since  the  phenylthio- 
urazole formed,  however,  is  always  in  equilibrium  with  the  phen- 
ylthiourazole anions  and  the  hydrogen  ions,  the  reaction  is 
not  stopped  short  of  completion  at  all,  but  only  made  slower. 
The  general  ideas  discussed  in  the  four  preceding  sections 
apply  equally  well  to  the  formation  of  this  non-reactive  ad- 
dition product,  and  hence  to  the  negative  catalysis  by  acids, 
bases  and  salts. 

In  the  above  discussion  of  catalysis  no  attention  has  been 
given  to  the  consideration  of  the  catalytic  action  of  finely 
divided  metals,  or  other  substances,  nor  to  the  reactions  brought 
about  by  enzymes.  Both  the  metals1  and  enzymes  probably 

1  Stock,  Gomolka  and  Heynemann:  Ber.  d.  chem.  Ges.,  40,  532.     Stock  and  Boden- 
stein:  Ibid.,  40,  570.     Rowe:  Z.  physik.  Chem.,  59,  41. 


102 

have  the  power  of  condensing  the  reaction  substances  on  their 
surfaces  and  hence  increasing  the  reaction  velocity  on  account 
of  this  increase  in  concentration  of  the  substances.  Of  course 
the  enzymes  and  metals  probably  have  also  specific  chemical1 
catalytic  action.  These  cases  in  the  study  of  catalysis  will 
be  reported  on  later,  in  more  detail. 

The  ideas  advanced  concerning  the  catalysis  by  acids  hold 
just  as  well  for  reactions  influenced  catalytically  by  bases  and 
metallic  alcoholates. 

Conclusions. 

1.  Work    on    the    reactions   between    urazoles    and    alkyl 
halides,  on  the  rearrangement  of  acetylhalogenaminobenzene 
derivatives,   on   the   reactions   of   carbonyl   compounds   with 
hydroxylamine  and  phenylhydrazine,  on  the  inversion  of  cane- 
sugar,  on  the  hydrolysis  of  amides,  and  on  the  formation  and 
saponification  of  esters  teaches  us  that  acids,  bases  and  salts 
may  act  as  positive  or  negative  catalyzers  and  cause  a   change 
(increase  or  decrease)  in  the  velocity  of  a  reaction  because  they 
bring  about  changes  (increase  or  •  decrease)  in  the  concentra- 
tions of  the  particular  ions  or  molecules  entering  into  the  re- 
action. 

2.  The    study    of  the  rearrangement  of  acetylchloramino- 
benzene  has  shown  that  the  second  law  of  catalysis  given  above 
does  not  hold  in  all  catalytic  reactions. 

3.  The  study  of  the  reactions  of  carbonyl  compounds  with 
hydroxylamine  has  shown  that  the  third  law  of  catalysis  given 
above  does  not  hold  in  all  catalytic  reactions. 

4.  A    general    discussion  of  catalytic  reactions  has  shown 
why  the  three  so-called  laws  of  catalysis  given  above  were 
deduced  from  the  experimental  material,  and  under  what  con- 
ditions they  do  or  do  not  hold  in  catalytic  reactions. 


OF  THE 

I    UNIVERSITY 

V       °F 

»  Acree  and  Hinkins:  Am.  Chem.  J.,  *8,  370. 


BIOGRAPHICAL. 


James  M.  Johnson  was  born  in  Newberry,  South  Carolina, 
August  15,  1883.  His  early  training  was  received  at  the 
Newberry  Graded  Schools.  He  entered  Newberry  College 
in  September,  1897,  as  a  sub-Freshman,  and  graduated  from 
that  institution  with  the  B.  S.  degree  in  1902,  and  with  the  M.  A. 
degree  in  1903. 

He  has  taught  as  follows :  Assistant  in  Chemistry,  Newberry 
College,  1902-3;  Principal,  Newberry  Graded  Schools,  1903-4; 
Carnegie  Research  Assistant  in  Johns  Hopkins  University, 
1906-7;  Lecture  Assistant  in  Johns  Hopkins  University 
during  1906-7. 

In  October,  1904,  he  entered  the  Johns  Hopkins  University 
as  a  graduate  student  in  Chemistry,  his  subordinate  subjects 
being  physical  chemistry  and  mathematics. 


DAY    AND    TO    $[no  S  °N  THE  POURTH 

Ovror.....  *'-00    ON     THE    SEVENTH     D!Y 


29  1932 
JUL  9    1936 


